You forgot OLPC, mithro. They have a good ideas list for doing games for the OLPC such as Mastermind, flash cards, typing tutor, and a small 3D game. I think both TP and OLPC sound like great GSoC projects so Hooray for FOSS Gaming!
Some of my readers ask me what a "Serial Port" is. The answer is: I don't know. Is it some kind of wine you have with breakfast?