Jeremie Carrier demonstrates a "15 note poly tempo pendulum." He describes it as "an amazing sweep of the rythmic subdivision spectrum!" I didn't understand those words, either, but I'll try to explain.
What he did was record himself 15 times, each time playing a steady beat of one note, but each recording is of a different note and a different beat. The tempos vary by only two beats per minute from one video to the next. Then all the videos were edited together. What we get is a beat that becomes more discordant, but then several of the notes will play a tune of sorts, then veer off from each other, and another set of notes will then stand out as if they were playing a tune. It's no symphony, but it gets more interesting as it goes. Carrier rang a bell to show us where a new "movement" begins. At five minutes and five seconds, all the notes and beats line up again as they were in the beginning. Cool.
As I listened, this started to sound familiar. The very first post I ever published at Neatorama was for a geometric music generator called the Whitney Music Box that produced this same effect.
-via Laughing Squid