FuturingWell, this is interesting.
Imogen Heap is part of a group who has developed a generative music app that will be available for purchase shortly. Here's how it works:
The Run-Time app generates a one-of-a-kind soundtrack for your run by recording ambient sound (your footsteps, your breathing, perhaps the chirping birds or honking cars in the background) and layering them onto an existing electronic track. Then, as you run, the app plays the song, adjusting the beats per minute so the music will automatically change tempo to match your running pace.
More details here.
I don't know if this app will actually be any good, but it does make me think about the future. Ten years from now, I see everyone walking around with headphones, listening to the soundtrack of their own life, which is generated as they simply live. I see music becoming more focused on a generative process via apps than something that is band-based. Transitive, like almost everything else is becoming. I don't like that idea, but I can see it happening.
In a more now sense, though, I find this kind of app as an exercise companion pretty irresistible. If it supported Bluetooth, I could theoretically use it when I swim. Borderline trance music seems like it would be highly conducive to extending exercise.
The fittest I've ever been in my life, though, was when I was listening to All Things Considered on headphones while I swam. The shows lasted an hour, and they were so engaging that I almost forgot I was exercising at all. So maybe I'm not the dreamy trance exercise guy after all.