Oh yeah, another arduino. So what is so special about this one? Well its developed by Adafruit, and its pretty small. They are not selling it yet, but its got allot of pinouts for its size. The board itself can be bought for $5 and another $6 in parts. My 2 cents, I have seen kickstarter projects for cheaper.
http://dangerousprototypes.com/2013/03/28/lira-an-arduino-compatible-microcontroller/