I normally don't like posting links to other sites..... but this is just plain cool:
http://www.instructables.com/id/EBZ3...3SL2/?ALLSTEPS
Apparently $600 later, you can have a CNC machine.
The documents included are very extensive.
Please Note!: I have not built one of these.... so I'm not sure how it actually turns out. Seems plausible though.
Jacob