ComputerCraft is a Minecraft mod with full SMP support which adds in game computers, which can be programmed using Lua and used to build advanced redstone contraptions. Each computer has a screen and a keyboard, a help system, six redstone inputs and outputs (which can be connected to bundled cables from the RedPower mod for a full 96-bits of I/O), a number of preinstalled utilities (including a fully playable text adventure based on Minecraft(!)), and a complete functioning file system!
All music used in this video is from the game Minecraft. The artist of the music is C418. If you enjoy the music go to http://c418.bandcamp.com/album/minecr... where you can buy the full album and support the artist!