Ballion by Juergen Urban is based on the C64 game Crillion. This is a Breakout clone where you have to destroy blocks with a ball.

If you copy a file music.mp3 to pandora/appdata/ballion/sound/, it will play the music. You can copy your own created levels to pandora/appdata/ballion/levels. The file for the first level is “level00”. You need to extract the ballion.pnd to get the existing levels and a description of the binary format.

http://boards.openpandora.org/index.php?%2Ftopic%2F7766-rebirth-competition-release-thread%2F