http://vonrafael.com/en/concept-hd.html

This cost 5000 euro's and it uses a belt drive. Granted the bike is way overpriced, but it would seem to prove a point. If a formula 1 engineer builds a bike that cost that much, and chooses to use a belt drive, it must be a pretty good system.

I am going to build a carbon fiber frame and have been seriously considering building it to accommodate a belt drive system, but now I am going to have to test ride one of these things first. One of my lbs has a trek sitting in the window that I'll check out tomorrow