From our friends at adafruit: “Celebrate the 20th anniversary of that classic gaming device by building your own with 3D printing and DIY electronics from adafruit. The 3D printed enclosure ( files here ) will house all the components and you can print it in your favorite color. Find out how to assemble and program this project by checking out the guide on the adafruit learning system.
See the article here:
Make a PiGRRL – Raspberry Pi Gameboy