Tim Diggle released the shoot-em-up game Survival Shmup for the GP2x.Release notes:

It’s shoot-em-up survival as you blast through a never-ending, increasingly difficult stream of enemies! Hone your skills to top the leaderboard! If anyone can grab a screen of this please get in touch. I have tried but fbgrab seems to crash the game.

http://archive.gp2x.de/cgi-bin/cfiles.cgi?0,1,0,0,1,1363