This is my second try at making a CNC Printer using 3 sleds from old optic drives.

@Source: https://www.dropbox.com/s/gftjl41ah6h...
@Source rudimentary explanation: https://www.dropbox.com/s/ujvwl47hta3...
Regarding requests for a tutorial. This is an old project and I currently don't have the time and means to help you guys out, so sorry for that. You can find the source code in the link above. For the driver I etched my own circuit board and put 3x HBridge chips on it (this is how one of those is wired http://42bots.com/wpcontent/uploads/...)
Using: Arduino Mega2560, 3x HBridge IC, 3x CD/DVD Sleds, 3x 2way switches (for manual stearing), wood, wiring.

I can print in freehand mode using switches.
The text was written as vectors.
The image was converted from a black and white bitmap to an array of the same size and from there converted into vectors.

Next step: Put a 1.5W laser on it... :D I've already ordered it on eBay.

If you need any info on how I made something specific, ask in the comment section.