Ben's been working on this one forever. This new version 2 Atari 800 laptop features a CF drive, a RS lcd, original Atari hardware and lots and lots of friggin soldering. That keyboard is hand wired, along with the CF adapter. Unlike the xbox 360 laptop, this one's got Ni-MH batteries that are good for about an hour of play.
http://www.hackaday.com/2006/12/16/ben-hecks-atari-800-laptop/