This is kinda related to the ObscureMentoring program, but the focus is less on long-term teaching than one-off knowledge sharing. The idea is to give people within the Obscure community an easy way to set up a searchable and browseable list of interests, things that they're willing to field random questions about.
For example, I (ColinMacDonald) am interested in urban design and architecture. I suspect there have got to be other Obscure people who are, too, but I don't know any of them. We have a community of smart people with a broad range of interests, but it can be hard to break the ice.
Livejournal has a mechanism for identifying shared interests, but they're all strangers. We have an actual community here, where people know each other. You can be a lot more open with folks because you have some connection to them, however tenuous. There's less worry about, "If I talk to this guy, is he going to become my new internet stalker?"
While a number of Obscure members have spread out across the world in recent years, we still have a strong core of people who live in the DC area, and can actually meet face-to-face.