Our sister from a different motha, Gina over at Lifehacker, got her Powerbook etched with a celtic knot this past weekend at the MAKE headquarters as part of the FOO Camp. She was nice enough to make a video of the very boring process in action.
The process is done using an Epilog laser cutter hooked up to a Windows machine (irony?) running Corel Draw to make the pretty pictures. Hit up the link here for more details on the laser-etching process and jump to see the video of Gina's Powerbook getting etchified.
Laser etching a Powerbook [Lifehacker]