Aardvark (http://vark.com) is a relatively new question-answering service that taps your extended online social network to get answers that can't be easily found with Google or other search engines. The question answering works both ways: not only do people answer questions for you, but you can help other people with their questions.
When you sign up, you're asked to offer up a few categories in which you have special knowledge. These might be things like your hometown, your job, or a hobby. They also give you the option to link to your Facebook account not only for building your network of people who can answer your questions, but they also use your Facebook profile to determine what some of your areas of expertise are.
When questions are asked, Aardvark labels it with a particular topic, which is then matched to see who in your network knows about that topic. Those people are politely asked over IM if they would be willing to answer a question about that topic, and given the chance to answer, skip it, or refer it to someone else (who may not even be registered with Aardvark yet). Interaction with the IM commands feels a little bit like playing Zork, which shouldn't be a problem for nerds like me who actually played Zork, but for people who don't know what I'm talking about it might take a little while to get used to. There is a web interface for asking your question, but it punts over to IM straightaway. I can understand wanting to stay focused on that channel, but some pretty cool things could be done with the extra flexibility you can get on the web.
Depending on the nature of the question, you usually receive an answer within five minutes, often multiple answers. Aardvark tells you who answered your question, and you can follow up with them by replying to Aardvark. It's a pretty neat system, which will grow in utility as the network of answerers expands and the system gets a chance to see who really answers questions about which topics.
I would encourage you to sign up and try it out the next time you're looking for recommendations or obscure knowledge that would be to hard to query from Google. I would also encourage you to answer questions from other people. It only takes a moment, and it's a satisfying feeling.