Well, the "logic" (rules, patterns, etc.) for generating the songs is exchangeable (the applet uses the file http://www.soundheli...Helix-Piano.xml by default, which is a relatively simple example).
SoundHelix is (sort of) the sequel to AlgoMusic. Same author, much more flexible, much better results. :)
Check out the SoundHelix audio examples here: http://www.soundheli.../audio-examples
Play around with the SoundHelix applet here: http://www.soundheli...lix-applet.jnlp
If you have...