littlesounddj.com
Little Sound Dj is a Game Boy music sequencer and editor. Its features include 4-channel, 4-bit Game Boy sound, dual sample playback, a waveform synthesizer and sync options for analog, Game Boy, MIDI and VST. The ROM image and manual are available as downloads, and the ROM can be used with a Game Boy emulator or on an original Game Boy via a flash cartridge.