Just bashed this up as a quick "test texture" thing.
Just run it, it will ask for the texture, you give it, and it'll simulate an Audiosurf sphere (without track etc, just spins left / right, up/down a bit)
Tested it up to 4096x2048.
Comparing it to Audiosurf, it looks fairly accurate for the range of view you'll get, so hopefully it'll be useful for those testing textures who don't want to run Audiosurf up all the time.
It uses OpenTK (
http://www.opentk.com) to render, which in turn uses OpenGL. It's written in C#, if anyone wants the source code, just ask. It's not complicated.
