Well, I had no idea this was such a novel concept. Thanks for all the replies so far. Yes, I think a co-op like the one I had in mind would work best in a place where there is a high cyclist density--especially an older-type town that matured before the car culture changed the compact designs of our cities into sprawling ooze. However, here in Austin we have a huge university as well as our share of folks who just like to do the right thing. And the co-op itself wouldn't really have to be that large, just an empty garage really. I'll have to do some market research... I guess I'll give the alma mater a ring and see if the Bike Co-op is still around.

--Chris