[rbalsdon]

I use this site a lot for background noise during the day when I could really use some new scenery. Some of the more subtle ones like the airship are really good for working and coding from horseback is a pretty unique experience.

myNoise.net is another good one. More tailored to workday background noise but a bit less interesting.

[FlyMoreRockets]

Coding from horseback sounds like an interesting experience.

You may also appreciate this:

http://www.imissmybar.com/