The programmer of Protein DS Scratch has been working hard. The program basically lets you sample songs (loops atm) and manipulate the sound, scratch the sample like a record etc. Watch the video here. We are still waiting for the next releases of Nitrotracker which are promised to feature a PSG which produces gameboy sounds which means it could turn out being an advanced version of LSDJ with it being a tracker already. (You can read the developer of Nitrotrackers blog here. Exciting times.