David Randolph from G4’s ATOS built a portable retro gaming system from two Eittek Power Player game sets, a Clarion VMA5894 car head rest video screen and a project box. Link. If this looks a little familiar, it is, the GameGrrl uses a low cost LCD and Nintendo controller instead. Between these two resources you’re likely to pull off this project and/or come up with new ideas.
Build Your Own Portable Retro Entertainment System