Check out these links if you are interested in computer-generated music!
Wolfram Tones: Variations on cellular automata, simple programs that produce very unpredictable results. A cellular automaton is made of a line of "cells" which each have a single value and two neighbors. The program computes the next cell based on the parent and its two neighbors. Output features stable local patterns and fractals such as the Sierpenski triangle. Wide variety of genres. MIDI format.
Fractal Tune Smithy: Annoying visual interface, fascinating results. Choose from an enormous selection of scales, rhythms, structures, etc. from all around the world. Results are often unclassifiable.
Whitney Music Box: Mesmerizing audio/visual display of harmonics and polyrhythms. Line of colored dots unfolds into a whirlpool of spiral shapes while musical scales perform in synchrony.