Water Music combines generative music with a 2d fluid simulation to give an effect of notes dripping across a mosiac pool.
http://openprocessing.org/visuals/?visualID=6458

The main sketch uses a couple of utility sketches that can easily be used elsewhere:
picture_pallet.pde makes a pallet from random colors in a picture file.
ripples.pde simulates defraction from waves in fluid and shadows the ripples for better effect over untextured colors.

I'd welcome comments.

Thanks Cedric.  I deleted the extra post.