[seancron]

I checked it out, and didn't end up signing up because I have no idea what it actually does.

I know you say it allows you to put people into circle, but how does it do that? Does it work with existing social networks, or is it an entirely new one that I would have to get my friends to use in order to take advantage of the circles?

It would probably be more useful at first to integrate with existing social networks because the only my techie friends would signup for a site like this. So in a way it's self organizing.