SunVox developer Alexander Zolotov shows off a relatively simple patch that generates infinitely unique melodies. Every single time he stops and restarts the pattern he gets something new out of it!
Each track is infinite and sounds differently every time you press PLAY.
Used functions: slow (subsonic) LFOs, probabilities, random notes and controllers (pattern effects 20-29), random phase setting at the beginning of the song, random interpolated waveform of LFO, prime numbers as the sizes of parallel patterns (in the set of MetaModules), etc.
SunVox itself: http://warmplace.ru/soft/sunvox