I love this math/music toy that Jeremy told me about: The “Whitney music box”.
“A flash animation showing the relationship between chromatics, harmonics, and even primes and non-primes.”
“A musical realization of the motion graphics of John Whitney as described in his book “digital harmony”
Be sure you try the other variations. And especially try Variation 17, which lets you crank the spiral yourself. Hmm… “Crank the spiral?” Sounds like some kind of surfing euphemism.