http://reprap.org/wiki/Main_Page - wiki page
http://www.youtube.com/watch?v=yzL391LfsvE&feature=related - sample video of what it does
http://www.youtube.com/watch?v=02myN2Y3iB4 - it reproducing itself
I figured if you haven't heard of it already, you might want to check it out. I'm currently trying to build one of these. It's a lot more involved (computer wise) to setup than I origionally planned, but i am making a lot of progress with the mechanics and 'some' of the electronics. The group may benifit after it is working. It makes copies of itself!! If any of you are interested in lending a hand getting it going, I could certaintly use the help.