This looks like a fun but potentially VERY dangerous project – we wish the sites linked below had included some common-sense safety warnings for potential builders. Please be conscious of friends and family members (especially the young ones) that might not fully appreciate the danger. If there are drunk people around, hide this thing, preferably under lock and key!
I recently made a mini CNC laser engraver using two DVD drives salvaged from old computers and <$10 extra parts bought on eBay. The controller of the CNC machine is a Raspberry Pi, a $35 credit card size computer. The engraver turns out to be pretty successful. So I am sharing it with everyone.
Full article here:
A Raspberry Pi controlled mini CNC Laser engraver (fun of DIY)
Raspi Mini Laser Engraver (Hack A Day)
Raspberry Pi Laser Engraver Created Using Two Old DVD Drives (video) (Geeky Gadgets)
Home-made CNC laser engraver (Raspberry Pi – this article actually does include a warning!)