Nearly 20 years after the original, a guy has developed an open source Gameboy made with fairly basic components. If you're interested, you can actually buy a kit with all you need here for $250. Or, if you're MacGyver, you could just make your own with a handful of paperclips, a disposable plastic plate, an iPhone, the batteries from your girlfriend's vibrator. Alternatively, if your girlfriends swears she doesn't have a special friend (despite your having heard a humming in the bathroom), you're going to need a potato.
Hit the jump for another picture and some videos.
Using the InputShield to make an Open Source Gameboy [antipastohw]
Thanks to "Also, in joystick operated related news ...I'll operate your joystick anytime. *wink wink*" Bernstein, who I have the feeling isn't a chick.