Looks like an amazingly cheap way to drive this particular reprap. Very cheap, and another step to reducing the amount of vitamins people use.
http://www.youtube.com/watch?v=PKkfn1GKuMo
WOW, that’s a better system, can’t wait till you are done so I can print one…
Tagging @Nicholas_Seward ; I shared it directly from youtube, forgot to share it from his link in the reprap community page. He’s the genius behind this. 
Add him to your circles, he’s got some amazing posts.
genius, very much so…can’t wait to build one…