[Minecraft SC #136] POEPIES

Core Rooms

There are several things every Minecraft shelter should have. They can be in your actual house, underground, or just within an area you know is safe from mobs. Keep in mind that multiple can be combined in one room.
Crafting Room
This is the single most important room and should be the first one built. A crafting room should include a crafting table, at least one furnace, and a sufficient number of chests containing common crafting materials found while mining, such as wood, cobblestone and iron.
This room should also contain a chest of supplies so you can quickly get what you need and leave without needing to enter the other side of your shelter to access it. This should be well-defended and well-hidden as it's generally a main entrance to your base. As an added precaution, you may build a snow golem or iron golem to guard your items.
Furnace Room
This is important if you are a big miner and adventurer as you can smelt large numbers of ores quickly. Make a large room and line the walls with furnaces, possibly keeping a chest of fuel inside as well. The benefit of having multiple furnaces is an extremely fast smelting time for many items, since each furnace is able to run independently. Having each furnace full of fuel is also helpful.
Store Room
A room full of chests for storing all of the dirt, cobblestone and other less-valuable materials that accumulates in your inventory while mining. This should be built once your main craft room's chests start to overflow. You may also build another store room, with a guarded and hidden entrance though this store room is usually filled with more valuable and rare materials, i.e. gold, iron, redstone, etc.
Note that as of Beta 1.8, chests are transparent, and can therefore be stacked on top of each other, saving space.
Entrance to your Mine
It's generally a good idea to put the entrance to your mine inside your shelter, simply so that, if you return at night, you won't have to make a mad dash to your house. It's probably a good idea to make sure your mine is well lit, or have a decent way you can enter your shelter from the mine or vice versa without mobs being able to do the same.
Back Door
The vast majority of basic shelter designs have only a single entrance, but you should always add a second if at all possible. This gives you another way in or out, especially if the main entry-way is temporarily too dangerous to use. (e.g. There is a Creeper at your front door.) Make it a very long passage way so you can sabotage the entrance from your old base to your secondary base. To cut the time taken to walk it use a railway powered by redstone for max speed. (You can also add traps like panels which release lava or water to stop a mob or simply blow up the track.)
Bedroom
Sleeping in a bed resets your spawn point to that bed.. Put beds in all homes to easily transfer spawn points. A bedroom often shares purpose with another room, such as a crafting room. It's a pretty good idea to share this with a secure bunker. It's a good idea to keep this room far from the outdoors, so you can sleep if there is a mob near the shelter.
Portal Room
It's best to have your portal inside your shelter, so you don't need to dash to your house, but it's no fun to have a Zombie Pigman spawn in your kitchen, as you could accidentally punch it, so your portal is best kept in its own room.
Brewery
Once you've been to the Nether and gathered some Blaze Rods, you can create a Brewery, which is simply a room with a Brewing Stand and a Cauldron(however a water source works just the same and doesn't run out). It is great to be able to brew some potions to prepare yourself for leaving your base. Include a chest with some potion ingredients such as sugar, redstone, blaze powder, nether wart, glowstone dust, spider eyes, magma cream and fermented spider eyes and a well as it is an unlimited water supply.
Positive Effect Potions and an example of a brewery can be found, at the brewing page.
Enchanting Room
After gathering some diamonds, obsidian, sugar cane, and leather (to make a book),you can build an Enchantment Table. This lets you enchant your items (See Enchanting for help on design), and since bookshelves give you higher level enchantments, this room could also be a good use for your sugar cane.
Farm
Unless playing on peaceful mode, you will want a source of food readily accessible from your shelter. It can be either inside or outside, but inside you have the advantage of accessing it safely, even at night. Start with wheat, but expand to other crops when you acquire them, such as pumpkin, cocoa beans, and melons. Having an animal farm gives you mob drops and experience as well as food. Sugar Cane and Cactus can also be farmed.
Tree Farm
Eventually, you will use up all the trees in your immediate surroundings, so you will want to replant them. Keep it well lit, both to keep away mobs and speed up the growth of trees. Birch is recommended, because it grows fastest, but Oak and Jungle trees are also a good choice, due to their apples and immense size respectively. It is difficult to build an indoors or underground tree farm that will supply your wood needs, unless you use bone meal.
Armory
An armory is a room near the front door with chests containing food, armor, and weapons, this is for easy access when you are going outside, and so you can quickly prepare yourself to retrieve your lost items. For an even faster alternative, this room consists of a number of Dispensers, activated by a single button or pressure plate, providing the adventurous player a way to get started immediately. This is very useful for exploring dangerous caves and going on night expeditions to get your dropped diamonds before they despawn.
[edit]Expansions

These projects, while not entirely mandatory, make your base more useful and interesting.
Control Room
This room is only useful when you have many redstone scattered in house. Be sure to put the room and control by Signs
Bakery
This is basically an expansion of a kitchen. You could build this and a kitchen,(suggested) and just connect them. You would use this to make cakes and bread. Place crafting table, chest, and maybe a display table? If you want to make large amounts of cakes, make a cake farm under or near the bakery.
Maze
This is mainly for if you get bored. It's quite simple and obvious how to build and use.
Mob XP Farm/Drop Collector
An XP farm uses water currents to push most mobs into a central area. With mobs in the nether, pistons are used. Use a piston crusher or a long drop to get the mobs to a 1/2 heart. Mobs can be killed by hand or with a splash potion of harming to get XP. Note: This is more efficient with multiple spawners, as more spawners mean more spawning opportunities. You will also obtain drops from each mob killed. This can also be done with large dark rooms with platforms. The mobs spawn and fall into water currents, where you can choose what happens to them once they are out of the spawning chamber.
Redstone Lab
A laboratory is a large, clear, secure area where you can safely test designs without distractions. When building large projects with complicated parts, it can save you time and effort if you test the ideas first.
Cake Factory
A cake farm simply provides the avenue to quickly produce cake by having the necessary ingredients nearby and produced in a close area, most commonly in one large factory type building. To make a cake factory make a Wheat Farm, Automatic Harvesting Sugar Cane Farm, an Automatic Egg Farm, and a cow in a cage (make the cage so you can milk the cow.). Place a crafting table and a chest. Once you have enough materials from the farms, start making cakes. This is a good thing to put under/next to a dining hall in SMP.
A simple video showing how to make an operate a cake farm is available by clicking here
Path/Road
How about building a road or a path between your buildings or to the nearest village? Remember to keep it well lit so no mobs spawn!
Cobblestone Generator
A cobblestone generator provides a safe and convenient way to gather cobblestone. They typically involve mixing water and lava. A tutorial of this is available here
Bunker
Sometimes called a panic room, a Bunker is a small room made of strong materials (obsidian for example) with an iron door with the open/close system inside the room. This room must have a bed, a crafting table, a furnace and also a chest with the basic materials (food, tools, and weapons are a must). It also has to have a high interior luminosity to avoid monsters spawning inside. It should also be only two blocks tall so endermen can't teleport inside.
Scout Tower
A cheap and safe way to survey the land. Note that these are mostly obsoleted by maps, should you have the resources to make them, although a map doesn't tell you if there are any aggressive mobs outside.
Beacon/Lighthouse
A tall tower with some sort of light source on the top means that you can see your base from a long distance away. Handy if you go exploring a lot, your spawn point is a long way from your base, or you have not made a bed yet.
Kennel
If you have tamed a lot of wolves, a kennel is a good place to keep them. A simple shed-like structure will suffice, but be sure to keep it well lit for the wolves' safety.
Well
A renewable water source is useful for a variety of projects. Put water in a 1x3 ditch and you can take water repeatedly from the center! For a more aesthetically pleasing pool, a 2x2x1 well works as well, and you can take water from any of the squares.
Wheat Farm/Greenhouse
A renewable source of food from the safety of your base is incredibly useful. If your base is underground or has an expansion underground it is highly recommended to make an underground farm. This will help avoid possible animal trampling or creepers blowing up part of your farm (See Farming for more information). For a tutorial on this click here
Melon Farm
A Melon farm produces the obvious, melon slices. Which can be used as a valuable food source that keeps your hunger bar up. For tutorials on creating an automatic melon farm click here.
Pumpkin Farm
A Pumpkin farm obviously provides pumpkins. These pumpkins can be used for souls for Snow & Iron Golems, Enderman protection as well as jack-o-lanterns and ,of course, simply for decoration. An automated pumpkin farm tutorial can be found by clicking here.
Tree Farm
Producing wood in your own base can eliminate a major reason for venturing in the dangerous outside. Make sure your farming room has a torch next to each sapling and has enough space upwards. A chest with axes, saplings, and spare wood can be helpful as well. See Tree Farming.
Mushroom Farm
A big room with flat floor. You can light your farm by torches or glowstone, placed on ceiling, to prevent mobs from appearing. Just make sure that there are no places on the floor where the light level is greater than 12. More about this can be found it by clicking here (Video Tutorial) or on the Mushroom Farming page. Alternatively, find a small cave or make one, put some mushrooms inside and completely seal it off without torches and check on it/clean it out. Also provides the drops from hostile mobs.
Sugarcane and Cactus Farms
Easier to manage but somewhat less useful than the above two projects, farming Sugarcane and cactus underground requires little effort. A cactus farm requires sand to grow, and Sugarcane needs to be properly irrigated with water within one block of it. If you don't want to spend lots of time harvesting your cactus, place a three-block-tall pillar next to where you want your cactus (See Farming for more info). Or click these links for a tutorial on creating these farms. Automated Cactus FarmAutomated Sugar Cane Farm
Indoor animal farm
Light up a large area with a grass floor. Then put two of the same kind of passive mobs (i.e., two pigs or two cows) inside. You can then breed them together and you can gather wool, leather, pork, beef and raw chicken safely. You might want to put trees inside so the animals feel more comfortable, or, if you're really ambitious, build a man-made forest. For an outdoor tutorial with the same concepts click here
Incinerator
A room with lava, for disposing of unwanted materials. A good way to do this is to create a two block high corridor with lava at the end, and a slab block just before the lava. This results in you being able to walk up to your incinerator but not into it, eliminating fear of death. Be careful with lava around flammable materials. You may replace the lava with a cactus block, or burning netherrack.

Example Incinerator Design
Obsidian Farm
Natural obsidian is dangerous to mine, let alone the difficulties associated with finding it. Make a long, narrow, enclosed pit to store lava in. The easiest way to get lava is in The Nether, so you may want a portal in this room as well. It is also possible to make redstone-to-obsidian converters. Basically you place redstone where the cobblestone is generated in a cobblestone generator before it forms another peice. Examples can be seen on YouTube
Minecart Hub
If you have active mines scattered over the place and use Minecarts to haul your stuff back to your base, dig out a universal stopping point under your base. Or, you could actually make a rail road hub outside or connected to your base.
Indoor fishing pond
This is very easy to make, and can be very useful, especially if you don't have a wheat farm yet. Just make a hole long enough to cast your fishing rod, around 8 blocks long and at least 2 blocks deep, and fill it with water.
Portal Room
Once you have at least 10 obsidian, either from mining it in a cavern or obtaining it though obsidian farming you can build a portal. Once built, activate it with a flint and steel, and you can travel to the nether. This can be used for fast travel and for getting lava, netherrack, Soul Sand and glowstone. Beware of ghasts, Zombie Pigmen and Blazes as well as Magma Cubes.
Mob Farming
A safe, renewable source of gunpowder, arrows, rotten flesh and bones. This makes exploring much safer and can provide the means for large amounts of explosives. Also see Mob Grinder.
Music Room
A room filled with note blocks to enjoy melodies. This can be made with or without redstone repeaters.
Library
Not only is it a great use for any excess sugarcane, a library can also add a bit of class to your home. Can double as an enchantment room.
Minecart Chest System
After a lot of days in Minecraft, you will soon have the ability to automate everything (farms, doors, etc). The most useful automation you can make is a Minecraft Chest System. You can simply craft Minecart with chests, Booster rails, and some rails, you can make a system to send your ores up your mine to your base, and have a minecart with more tools come back to you.
Gravel-to-Flint room
Once you have many stacks of gravel, it can be useful to convert most (leave some for mining) of your gravel into flint. This is just a big empty room (a 4X4X4 space holds a stack of blocks), which you fill with gravel, before destroying the gravel, getting some flint in the process. It is most efficient to do this 10 - 15 times for every 20 stacks, though about 5 for 10 stacks, and 30 for 50 or so stacks. This room may include a chest with shovels, as well as ingredients and a crafting table for quick production of arrows, and flint and steel.
Target Practice Rooms (optional)
Make this room dimly lit, so hostile mobs can spawn, when you enter this room, always close the doors when entering and exiting, arm yourself and kill the mobs in there. Light the entrance area with torches. This will help you gain XP and loot.
Target Practice Room (non-hostile)
Make this room with a supply of bows, arrows, and several colorful blocks, such as dyed wool, (to determine distance rank) at different distances with a levers on each one facing you with each one hooked up to a redstone lamp.
[edit]Defense

These additions make your base safer and provide a certain amount of entertainment.
Self-Destruct Button
Pretty Self-Explanatory,a button that blows up your base and kills the mobs and/or Griefers.
Murder Holes
First, dig a 2 block deep hole in the ground. Dig another hole 3 blocks deep, 1 block away from the first hole. Dig out the block that separates the bottom of the 2-deep hole with the middle of the 3-deep. If done correctly, this should allow all mobs (except for spiders) to fall into the 2 block hole. Then, you simply go into the 3 block hole and attack their feet. Murder Holes often function best alongside a perimeter wall of some sort, with the 2 deep outside and the 3 deep inside. An extra addition to this is to make a large amount of murder holes, and form a tunnel system of sorts, so you can watch multiple holes at once. These were featured by Paulsoaresjr in his minecraft tutorial videos. This works best before version 1.3 because the mobs have new coding that makes it hard to get them to fall in holes. They will simply navigate around holes deeper than 2 blocks.
Skylight
Although this may not sound like much of a defence, building a small skylight above your entrance/exit will allow you to easily see any mobs (Especially spiders) waiting to pounce on you from above.
Anti Hostile Mob Passageway
You can use the fact that snowballs push hostile mobs, by building a 1-wide bridge over lava and putting snow golems on the side (see gallery). The player and passive mobs can pass through safely, while hostile mobs will be pushed to the lava by the snowgolems' snowballs.
Overhang
Since Spiders can climb walls, a base needs to have either a ceiling or an overhang along the outside walls to be safe. The walls must be at least four blocks high (since spiders can jump up to three blocks high). Of course, a closed roof with a lava pond on top is also nice...
Perimeter
Adding torches around your base can reduce the amount of monsters that spawn nearby, so add some light to your lawn! You can also use fences, cacti, and burning netherrack to keep enemies out. Just remember that spiders can jump your fences.
Floodgate
Using a fairly simple redstone circuit connected to a lever at one end, and one or more pistons at the other end, you'll be able to build some simple floodgates. If you extend the pistons first, and then place water, or even lava behind it, you can get rid of or even kill any mob passing by pulling the lever and letting the water or lava flow! For a quick morning mob clean-up and a strong sense of catharsis, you can place lava floodgates surrounding your entire shelter, facing out. One throw of the lever reduces the surrounding landscape to a barren, hellish wasteland! Not to be used in wooded areas.
Relax room
Lets say you want to relax and see some monsters die, well this is the room for that, all you have to do is find a spawner, extend the dungeon, replace one of the walls with four block thick glass, then inside there put a lava blade, then outside of there put a chair and some light then you have it.
Moat
The simplest of these is a "dry moat" or trench, a couple layers deep so that skeletons and zombies can't get across. This can provide you with a reasonably safe area that is outside. This can be filled with water to push the enemies to a mob grinder, or simply filled with lava which has more dramatic and obvious effects. Please note: It might not be a good idea to use lava when having a shelter built out flammable blocks such as wood, wool or wooden planks. Tower shelters would do well to have a three-block deep water moat to break the player's fall so they can safely fall to the bottom.
Lake
If a moat does not feel sufficient, build a lake around your base, preferably several levels below the entry level and with a bridge to allow easy access back and forth. Again, it can be water, or, if you want a dramatic flair, use lava. Remember to protect the bridge well, though, and be sure you are protected from within the island in case you miss a spawner. Making a drawbridge out of trapdoors is a fun alternative to the actual bridge.
Archery Tower
If you have a plentiful supply of arrows, building a small tower to pick off nearby monsters can be fun and provide useful resources such as gunpowder.
Dispenser Turret
Put a dispenser with some arrows at your desired location (preferably next to a door) and a Stone Button/Lever/Pressure Plate attached to it. This is handy if mobs want to pay you a visit.
Traps
If you're not satisfied with moats or a perimeter fence, consider adding a trap or two. If you're up to a challenge (and on a SMP server), you could even make an entire trap, designed to look like a base! Dark rooms with no way out for mob spawning, entire mazes made of glass, and traps using pistons and lava. The possibilities are endless.
Wall
Build a large wall, light the area inside and you can live "hostile free".
Drawbridge
Using trapdoors, some redstone, and switches, a simple drawbridge can be made. Dig a moat around your base and make sure it is too long to jump across. Now, make short walls next to your entrance. Depending on whether you have a single door or double door, you will have to use one row or two rows of trapdoors respectively. Run redstone next to the trapdoors and connect them to switches inside your base, then cover up the redstone walls. This prevents mobs from getting close to your door while you are inside your base, but the bridge will have to be left open while outside your base, otherwise you'll have to find another way back in. Alternatively, you can make a T Flip-Flop gate and place another switch outside your house to trigger the drawbridge from anywhere.
Sticky Piston Drawbridge

Sticky Piston Drawbridge, blue shows water level
It is possible to make a drawbridge using sticky pistons that is very difficult for a mob to cross. This draw bridge also involves the use of a moat or lake. A knowledge of redstone logic gates and how power is supplied to blocks is needed as the mechanism uses multiple redstone repeaters, NOT Gates and a T-Flip Flop. Using the T-Flip Flop one can wire the drawbridge so that it becomes accessible or inaccessible with the touch of a button from either side of the bridge. When the player(s) wants to cross the button is pressed causing both ends of the drawbridge and the center to be even allowing the player(s) to cross. When activated to keep mobs out both ends of the drawbridge are raised 1 block higher than the water level making it impossible to jump from the water to dry land and the center blocks are lowered 1 below the water level causing the center area to flood. Assuming both areas are properly lit and secured this creates an impassable entrance to one's base.
Secure Waterfront
Because zombies and skeletons can survive sunlight in water and hostile mobs can swim, if you have a base on the coast it's a good idea to make sure it isn't vulnerable to mob attack. Building canals, lighting nearby islands, and building walls on areas of water you don't use can stop very rare, but still as deadly, attacks from the sea.
Blast shield
About 3 or 4 layers of some cheap material (e.g. dirt) placed on the house will make it ugly, but it prevents creepers from doing any damage to your house. Alternatively, you could use 1 layer of obsidian instead.
Self-Rebuilding Wall
It's possible to apply the idea of a cobblestone generator and use pistons to make it automatically rebuild damaged walls. Generally more effort than it's worth, but very neat-looking.
Land Mines
If you like to blow up stuff, you might like this. All you need is a lot of pressure plates (wood) and TNT. Once you found your spot dig two blocks down. Then place the TNT then another block, then the place the pressure plate. You can have a big mine field but usually more effort than it's worth.
TNT Cannon
TNT cannons are a good destructive way to take out mobs. Make a TNT cannon and have a chest full of TNT. For more detail go to Tutorials/TNT Cannons.
Iron Golem Trap
If you have plentiful iron, you can create a separate room containing multiple iron golems. This can be opened via a piston door to allow iron golems into a courtyard or garden. This will allow them to be sent to kill zombies if your house is under siege.
Cactus Wall
If you have a small house near or in the desert, and you want some more protection because you're just starting out, or if you're a veteran and you want a cheap, effective wall, then this is the wall for you. It's basically composed of cactus blocks, placed about 3 blocks high, and all around your base in a way like this:
o o o o o o o o
and only make one path to your door, this will trip up most mobs, other than skeletons because they shoot, and spiders, and they tend to jump over it, but it's an excellent defense for a beginner.
Outer Walls
The best material to construct these are stone, stone brick or brick. They should be at least 4 blocks high and 2 wooden doors for the exit. Make sure to build ramparts and cover walls, and fill with lava/water. Also have a x1x1x1 moat of lava/water with a torch in front like this:
w
I w
O
where i= torch, w=wall and o=water
Weaponry room
This is a room you can solely use to make weapons and store them. You'll want a crafting table and some chests for materials. This is useful since you can then use your original crafting room for things other than weapons, therefore leaving more space for such. Some holes in the side would be useful for sniping all the mobs and creepers outside.
[edit]Other Ideas

There are infinite possibilities in Minecraft. These ideas are not always functional but can be fun to make and have.
City
This is a good way to put torches, cobblestone, gravel, and wood to use. First, you should dig out a road (as wide and long as you want it) then fill the holes in with gravel, then build as many cabins as you want in each cabin put a table, a chair, and a chest, then light it up and put a wooden door on each one. Then build a restaurant, this should have some chairs and tables, and in the kitchen put a chest full of food and coal, then put furnaces in the kitchen, if you want to make is really nice add outdoor seating, if your on multiplayer charge people to eat there. Then add a store (only build this if your on multiplayer) it should have lots of sorted chests, its recommended hire a guard to guard the valuables. Now add your house, this should have a bed, a crafting table and a chest, and a bathroom, and anything else you want. Now add a fountain in the center of the city. Finally add a bunch of mini houses containing chests, and a crafting table. wait for the next update so villagers can spawn in your village.
Museum
This can be about various things. Minecraft, you, your worlds, or a favorite mob can be among ideas.
If you want it to look grand on the outside, place large pillars around it. Also, a grand staircase to a large front entrance helps.
If you build this in multiplayer, hire guards/security to guard your beautiful creation.
Secret Base
If you are in SMP, you don't want anyone getting into an underground base, right? Well, dig down at least three blocks and make a room. Then get out and put a piece of dirt over the entrance and place a sapling. Put bonemeal on it. Then dig the piece of dirt out and make a hill one block away from the tree. Dig one block into the hill and place sticky pistons so that when they come out they stick to the tree trunks and pull it back or forth, thus opening the entrance and closing it. After that, you need to expand the base so it's actually useful!
Zoo
Ever wanted an area to see all the mobs in their epic glory? Build this! Its BEST if you use Bricks, Stone Bricks, or Stone. You'll also need fences or glass, and signs. First, build various pens for Mobs. Make it comfy, so they look, well, comfortable.Place glass on all sides, or just one. Alliteratively, you could make a deep pit and put mobs in it. Put a fence around the outside.
When you're done with pens, place paths guiding players around. If you want in nice, place large fountains, flowers and hidden Noteblocks around. If you want it realistic, build restaurants, statues, and gift shops around.
Natural Vacation beach
This is VERY easy. Simply find a beach, dig out a large area, fill it with sand, and your own touches, and tada! You're done.
Man-made Vacation Beach
This is a bit harder then the natural version. Dig out a large area. Make it AT LEAST 60 x 60 blocks big, slowly getting deeper. Fill the outer shore with sand, add your touches and tada! You're done!
Sand Castle
Build a Big Castle of sand with many rooms,chambers and what ever you many desire. Add a Moat, sniping towers or other defenses or a nice sand strong hold.
Camouflage
This really serves no purpose in singleplayer. Simply place tall grass, vines, leaves, trees, and water on and around your base(s). It can give it a kind of cool look, depending on how well you do.
A Water "Fall"
If you have a tall base and you want to get down faster, make a 3 block deep hole on the ground and fill it with water, so you can jump down safely.
Add underground floors to your shelter.
Using this gives you a chance to find resources, and in the case of invasion by mobs, it will always provide a safer spot. Underground floors are also useful for making mob grinders or animal farms. If you're really good, add a whole back up shelter under ground. If you like to be safe, add multiple bunkers, but hide a super safe and secret bunker. You could also make a part of the floor out of glass in the same spot on each floor, so you can see all the way down, and it looks nice if you do it right.
Add above-ground floors to your shelter.
It is normally advised that you do this after building underground floors, especially if you have a ton of resources (after mining the basement out). These floors could even give you a chance to "snipe" some creepers and spiders in the morning.
Balcony
Place your balcony so that it has a nice view! Add a chest with bows and arrows for quick mob sniping. Useful for a variety of things, from providing a point for easy kills to enjoying views.
Landing and Takeoff Platforms
If playing with flying enabled (for example, in Creative Mode) you can create platforms at the same height on multiple buildings for easy flight between the upper levels of different locations. This works great in tree-forts, cities, and anywhere that multiple balconies are otherwise unconnected.
Remake it out of a different material
Install luxurious violet carpeting for the bedroom. Give your craft room a nice glass roof. Rebuild the armoury out of obsidian. Redo your outer walls in smooth stone. Add a second story to your library.
Make another base in a new location
Having more than one base helps if you need to travel farther to get resources. A base next to your spawn point is helpful if you built your main base far away and you died at night. A base in a desert can provide sand, and a base in a tundra can provide snow. A base hovering in the sky can provide entertainment, especially if mobs spawn on the edge of it. A great idea is to connect them with nether portals that have a secure hallway in the nether.
An emergency kit
In case you need to quickly gear up and run back to get dropped gear. Perhaps a sword, cake or a stack of porkchops, a stack of torches, and maybe some TNT? A more advanced kit can be made from dispensers that give you items at the click of a button or a step on a pressure plate, although arrows and torches will still have to be accessed from a chest or two (if you want the whole stack).
Add an escape tunnel
You never know, a creeper might one day get you. It could also be used to lead to a secondary base.
Lava lamp
Simply make a hollow space out of glass and fill it with lava. An efficient method is to run a vertical column through many floors powered by a single lava block at the top. You can also make one of these high above your base to mark it from afar. If your house is made out of flammable blocks, this isn't recommended.
Quarry
A Quarry yields very large amounts of materials such as cobblestone and dirt to make your buildings, and coal and iron to make tools and torches. It can require several days of game-play to finish building. Some rarer materials like gold can be found as well. See the Quarry page for instructions.
Mining shaft sunroof
Making a sunroof that points directly down your mining shaft has its advantages: you will be able to tell the time of day more easily, and burn mobs like zombies and skeletons. The sunroof can also provide enough light to discourage other mobs from spawning in your mine.
Lava beacon
Make a large pillar of stone or any non-flammable material and pour a lava bucket on it. It helps when you are a long way from home. Make sure not to build it too close to your base if it's made out of a flammable material.
Glass/lava floors
No mobs can spawn on glass floors, making for a handy alternative to a well-lit shelter. Light is still important, though - you could even have a 1 block high space below all glass blocks on the floor and pour lava there. This will keep your shelter visible and provide a fancy, creepy feel.
Doorbell
Players (and mobs) entering your house without your knowledge is a pain, that's why you need a doorbell. When a mob or player steps on the pressure plate the note block will play a sound, and you can make this more sophisticated making chimes or even a whole song that play upon entering.
If you have multiple entrances to your base, place different blocks under each note block to make sure that if a creeper comes to your west entrance, you don't get blown up when you try to run away through that door.
Blinker Beacon
A more technical variation on the Lighthouse - the light blinks on and off like a real lighthouse.
You may also use a minecart rail system, which can be made so you put down rails in a square(4 rails on every side), then put down a booster and detector rail, power the booster, and connect the detector rail to the torches you want to blink with redstone. Place a minecart on the booster and it will loop forever.
This can be used to blink multiple torches with the same system, and does not require maintenance. You can connect more detector rails for faster blinking speed.
Outpost
Make a small room somewhere away from your base. You can include a bed, a cake on a table (for food), a crafting table, a furnace and a chest. This is helpful as a simple second shelter, and the cake is a useful source for restoring the hunger-bar if it gets low. Add a door and windows to know when that creeper is staking out your door.
Dock/Harbour
If you find yourself using boats in a general area often, making a dock or two is a good idea. They can help prevent your boats from drifting off into the ocean, or slamming into a wall when you exit, thus breaking the boat. Dispensers can also be placed here and filled with boats for convenience. Chests filled with boats are a good idea too. There are several ways to make useful docks.
Placing half-blocks in the water. When a boat moves on top, it will slow down and stop immediately. Half blocks are shorter, so your boat will not collide with it and break.
Warning: it is recommended to only use this method on Peaceful difficulty and to land on the half blocks at a low speed, instant death is possible when landing on half blocks at maximum speed.
A closed dock. One type of dock is by making a small area (2x3 or larger) that is filled with water. You can place doors in the water, allowing you to ensure your boat will not drift off. Soul Sand is a suggested building material, as it will prevent all of the impact damage from colliding with a wall made out of it.
Water currents. By using a bucket to remove the top layer in 2+ deep water, you will create a + shaped water current flowing towards the centre. You can use this to hold boats, while still being able to escape somewhat easily. This design does not always prevent the boats from moving if you or a mob bumps into it, but will help prevent it from drifting away
Fridge
Create a fridge by placing a dispenser on the ground, a block on it and a button on the side of the block to quickly get something to eat when you're starved. Add a door in front of the dispenser if you feel it would look better, or if you just like the idea.
Miniature zen garden
Either above the surface or underground, create decorative minimalistic works of art using water currents, plants/crops/flowers, sand, clever use of fenceposts, signs, torches, etc.
Fountain
You need 22 stone and a bucket of water. Make a 5 by 5 square with the nine in the middle taken out so the water won't spill, then make a 4 block high pillar in the middle and place the water on top of the highest block. Taking out the stone pillar in the middle of the fountain can look nice, and placing half-blocks around the stone blocks can look fairly cool.
Piston Doors
These are very cool looking. Have these anywhere in your house: library, craft room, furnace room, you name it. All you need is redstone, sticky pistons, and levers. Be sure to keep them hidden if the rooms are secret.
Tunnel to a Stronghold
After you found a stronghold make a tunnel to it. Easy way to get to The End. Keep it well lit and defended so that the creeper you ran into in the stronghold can't follow you back to your base and blow up.
Add a carpet
You can spice up your base by adding a carpet made out of coloured wool. Make sure that fire and lava aren't less than two blocks from the carpet otherwise, well, your carpet will go up in flames! Bright colours, like red, blue and purple are recommended, because black and gray carpets don't have the same feel.
Roller Coaster
If you have enough resources, build a roller coaster out of rails. Add twists, turns, steep climbs and falls. Use booster rails to keep it running fast. This is a decent way to keep occupied while you have nothing else to do in the vast world of Minecraft. Useful on SMP- you can charge other players to ride.
Sky Base
Create a base floating in the sky with no bridges or stairs connecting it to land. Of course, it doesn't have to be this way to build it! The no-connections idea can be accomplished with waterfalls, piston elevators, and nether portals. Add other sky islands nearby with bridges to connect them, and it'll be like you never left the ground! If you truly don't want any connections to land, even with the waterfalls and nether portals and elevators, gather up all the resources you'll need and seal yourself away in the sky. (But make sure you have a bed up there in case you die.) For extra entertainment, make a smaller island and plunge it into darkness, and watch mobs walk right off. To make it even more entertaining, place some arrow dispensers hooked up to pressure plates on the island, and even make signs all along the edge.
Battle Arena
The first thing you must do is find a mob spawner. Then seal off any extra entrances and place a door at the last remaining one. Maybe make the dungeon a little bigger, to provide for more fun and monster spawns. Finally, make a lobby with chests full of equipment (swords, bows and arrows), potions and food. Now you can fight that specific mob whether for experience or drops for as long as you want! Include beds if it is a long way away from your base, so that if you die you won't have to walk for ages just to find it again. If in SMP, add a lock on the lobby and another lobby where other players can pay you to fight that mob. This is handy to build in abandoned mineshafts, wherever you find a cave spider spawner.
Railway
Make a long tunnel to fit from one to any amount of minecarts, then use minecarts with furnaces to propel the 'train'. You can also use powered rails, but for that you'll have to find gold and redstone. Be sure to add emergency chests to the side of the track and fill them with coal to power your minecart so you don't get stranded. Adding food and weapons in these chests is a good idea, in case you get stranded and have to fight some zombies to make it to your shelter. This is fun for SMP and single-player and you can go across the land quickly. Don't make your railway aboveground; you will constantly be attacked by creepers. However, covering the railway with blocks (such as you would make a house) can solve this problem, alternatively you could build a 3 block wide track that is elevated off the ground 2-45 blocks. This option is very cool and provides great views but is not suitable for SMP. Make stations for your favorite landmarks (big mountains, your house, etc).
Minehouse
Make one of these if you have a long and deep mine and have to constantly run up and down long tunnels to drop off your bounty and sleep for the night. You need to make a small cottage in the middle of your mine, but digging out a room(s) in the side of a wall works fine as well. Adding a door, windows and plenty of light will reduce the chance of being ambushed when you wake up in the morning. It must have a chest with food, picks, and shovels, as well as rare items that you don't want to lose while mining. Having multiple chests in a back room to store your excess dirt, gravel, cobblestone and ores is handy if your main chest is getting crowded and you'll be down in your mine for a while yet. A crafting table, multiple furnaces for quickly smelting items, and a bed are always good to have inside. You can also include an Enchantment Table for quick enchanting of tools and armor, especially if your favorite Efficiency IV/Silk Touch I diamond pick got burnt in the pit of lava that also stole some redstone.
Pool
Make a pit of any shape or depth, but a small, rectangular design that is 2 blocks deep is recommended. Fill it with water. And now you've got your very own pool. And if your extra careful, you can make it with lava instead. Also it lights up that area of your base and looks good.
Park Square
Make fences around a 20x50x15 area, put a garden, and a wool statue with a stone base. You can use bone meal on the grass that makes up your square to make tall grass and flowers appear. Adding pathways of blocks like stone brick shows players where they can go and adds a nice touch.
Work Tents
If you feel that you're running out of inventory space frequently during above ground projects, build a work tent. Make a 4x4 fence box, add a door and wooden roof, and place lots of chests. Add a least 1 furnace and a workbench. Dig a little ditch in case a skeleton or spider appears. This can double as a safe-house/tent.
Mining Rig
Create a platform on top of a relatively flat surface or mountain. Dig out a trench in the middle of it and place redstone on either side connect the redstone to a single button and fill the trench with TNT. All you need to do is to press the button and you will begin a pit that leads to the bottom of the world. A automatic reloader can be added via sand and pistons.(Can be easily repurposed into a cannon)
Toilet
You never know when nature will call. You can make a small toilet out of water and sticky pistons or trapdoors. It can be used as a garbage disposal or just for laughs. Its basically just a waste of time and resources.
Mob aquarium
A glass box with a mob spawning room above it with a connecting hole so mobs spawn and fall in.
Testing room
Saw this great creation online but never knew how to build it? Following a guide how to build things without risks? Want to warm up on traps and other things with no damage to your shelter? A testing room has various things you have never hoped to build before. cover with obsidian to reduce damage to shelter, or make a new world to test new things. Who knows? Maybe they can work as good memories
Canal
This is a good way to get around if you live in the middle of a huge island. The best kind is a 2x3 extending where ever you need to go.
Landing Site (Litteral)
So if you have procured yourself some Mods you can actually make a real landing site. Once you've got a plane or two you will want to store them somewhere away from the creepers or other players. So behind your base, get black wool flooring for at least a 30x30 area and put Nether Brick Fences or just normal Fences all around it. Then, build a dome out of glass blocks big enough to get a plane into it. Repeat the third step for the rest of your planes.
[edit]SMP-only Ideas

These ideas are quite pointless if you play by yourself (unless you have a VERY smart mod!), but are fun additions to a multiplayer server!
Party room(s)
this is a large room(or small rooms) dimly lit by redstone torches and have a big ceiling, you can have a table and chairs or a bar and you can charge people to have party's there.
Mailbox
Simply put a chest on top of a fence post, then other players can give you gifts. Be wary of thieves though! After 1.3 you can leave messages as books.
Bank
Make a bank to store items. Players could pay Gold or Diamond to store their valuable items in a 'vault'. If you're really ambitious, the Vault could be lined with lava or obsidian (or bedrock if you're an Admin) to make it super secure.

Tollhouse
For bridges that lead to your property.
Inn/Guesthouse
Build a large and well-defended structure with private rooms each containing a bed and chest (possibly a furnace and crafting table too). For additional style points, decorate the rooms nicely. Use a locking mod, and charge people to stay at the inn; when they rent a room, add them to the list of people who can unlock the door and chest. You may want to hire people to man the front desk, keep records and collect bills. This is especially useful if you build it near a dungeon, as players will want to have a well-protected "base camp" when setting off to explore.
Army
Make an army from other players. People can pay the army in valuables to protect their homes. Charge based on location and how long.
National Park
Corner off a HUGE area of land with big mountains and amazing caves on a multiplayer server. Put in information signs for landmarks and charge people to visit. Make some camp-sites to house players while exploring, and put chests with food or weapons in the camp-sites. Be sure that players give back any items they use.
SMP-Railway
Charge other players to ride on it, a perfect way to get coal or emeralds. Make a deluxe version for long journeys. Make windows in the tunnel. Another idea is to make a subway. See Tutorials/Train Station for more information.
Spleef Arena
Great way to have some fun with your friends on multiplayer. You should make a Snow Golem room to be able to collect snow balls easy to craft into snow blocks. You can bet on games, build a score board and have stands for people to watch. You can also make it so the loser faces a little more punishment and humiliation by making the bottom out of lava so if someone falls they will burn to death. This makes it a little more fun and pleasurable to watch your opponent burn. You could also make a long drop that kills the loser, and the winner can take all the dropped items after the game.
PvP Combat Arena
Create a huge room and fill it with obstacles and platforms. Make a roof with beds on it, that players will respawn in, and chests to take equipment from. Make holes in the roof to allow players to enter the arena at different places. Use ladders or water holes to prevent falling damage. You can give the arena a theme, like a forest, and decide what equipment should be available when players respawn.
Courtroom
Useful on any server with a problem with griefers (though they might just go greif the courtroom when they are teleported/summoned there), stealing, or pvp (though they might pvp all the players in the room). A courtroom usually involves a chair or place for the judge, the jury, the defendant, and others wishing to speak. It is much easier to maintain a trial with everyone there in the Courtroom rather than just over chat, as there will be no distractions and the defendant and others can be kept under control. Depending on the government system chosen, the jury can vote on the punishment, or the final say can be up to the judge. Due to number restraints, it will often be hard to have a completely unbiased jury, but try to have at least one person who wasn't involved or biased. If the defendant is deemed guilty, a punishment will be decided, which can range from having to give back what they stole or repair the damage griefed, to a restraining order, a banishment from the town, or even being banned from the server. Optionally, you can have a Records Room to keep track of the trail using a Book and Quill from Snapshot 12w17a (just be wary of offenders trying to clear their name by destroying the book or editing it), but can also be tracked with .txt files outside the game (which might be a better idea if things are really geting out of hand).
Jail
The Jail/Detention Center is where criminals go if the punishment agreed on is not an execution/banishment/ban. Build a secure room with traps outside cells to prevent criminals from escaping, via bugs and digging, like lava flowing from the top of the jail.
It is very hard to make a secure jail without using Bedrock or obsidian . An alternative is to have the walls of the room constantly being moved by pistons, so the player has no time to break through them. However, this will create a lot of lag. You can make a regenerating wall using water and lava as well. Be warned, however, that if the spawn is outside the jail, the criminal can use the /kill command to escape or blow themself up with TNT. Also NEVER send a admin to jail without reverting their admin status first or they can just switch themself to creative mode and mine the thing you made the jail out of.
Restaurant
The restaurant can be a place where people pay in goods or money for you to give then food. You could plop a few chairs down too and make a kitchen full of furnaces and chests full of food. Out the back of the restaurant you can make a farm to get some wheat or pumpkin maybe even Melons!