My friend and co-geek Mads Høbye has been improving on an old synth project that I started some years back. He has now made an instructable to to share it with the internets.
We are planning to make further improvements and make it into a proper Arduino library.
Some sound demos here: test1 test2 sequencer1 sequencer2 sequencer3 demo1 demo2
Do any of the demos/songs above exist as midi files ? I'm turning this into a midi synth/sequence player, and would really like to get hold of the midi files to test it on. If possible please share, or pm me.