Yes. I've been infatuated with this idea for 3 years now. Specifically, having the groups centered around threaded forum-like discussion. So many times I've wanted to throw up a temporary forum online, and I just could never find an easy enough way to do it that didn't require lengthy registration and administration.

It would be nice if I could just tell someone, go to "foobar.com/<some word>" and we'll discuss it there.

I have a killer domain for the idea, but sadly have always been too busy working on other projects. To tell the truth, I'm a bit intimidated by working on forum software. Last time I tried, I feature-creeped myself to burn-out.