Brain Party from Hudzilla Games has been released as open source for Linux some days ago. A thread on t.m.o suggested somebody port this over to Maemo. An afternoon of tinkering later (and with the help of Javispedro's SDL-GLES library), I've got the game to run on the N900 (see the patch for details on the changes - as you can see, the original source code is pretty clean, so porting was mostly straightforward after being told about SDL-GLES, fixing a parameter for glTexImage2D and doing some math to scale the game to the N900's screen and scale the input coordinates the same way). The package is currently in Extras-Devel, soon to be promoted to Extras-Testing. In the mean time, you can grab binary and source packages from this page (use apt-get -f install afterwards to satisfy dependencies).
Please test it and vote for it on the Maemo.org package page when it enters Extras-Testing (did you know that you can follow @maemoextras on Twitter to see packages entering Extras-Testing and Extras? Now you do..).
It's good to see developers porting their games to Linux and open sourcing them, which makes learning from their code and porting the games to other platforms very easy. If you like the game, please support the developers by purchasing Brain Party for the iPhone (you probably don't have an iPhone, so show the N900 game off to your freedom-hating friends and tell them that they should purchase the game for their iPhone/iPod touch on the App Store). The game is also available for Windows Mobile and Xbox 360.
