I was reminded yesterday of how much I love Steve Reich's tape loops. I'm not sure if you can call it "music" in the normal sense of the word. I think Reich is a genius because he makes you find music out of just noise. He takes these simple tape recordings of street preachers or interviews and loops them over and over again. In some of the tracks, you'll hear two loops going on at once, and one of them is just the tiniest bit faster than the other. It doesn't make much of a difference at first, but after a while you begin to hear the recordings stretch apart. First as an echo, but eventually whole words will be out of sync.
The songs are rather long and somewhat monotonous, but I just have to keep listening. It's kind of spooky.