Thanks to a Polyphonic Spree ad in Wired Magazine (who says advertising doesnt work) just found this:
http://www.ringblender.com/blender.html
This site allows fans of the band to take pre-selected tracks and samples and make their own ringtones, share them with friends and download to their phones.
DIY? Check.
Band that values its fans? Check.
Simple, well-done execution? Check.