Did you know Wikipedia has a reference desk?
The Wikipedia reference desk works like a library reference desk. Users leave questions on the reference desk and Wikipedia volunteers work to help you find the information you need.
Questions/answers are broken up into categories, and are both interesting and sophisticated. I also like the format of crowdsourcing answers - even when someone had given what I thought was a great answer, subsequent responders added new information or aspects that were useful.
Actually, it reminded me of any other online forum, which I use all the time for answering questions (especially for coding problems or frustrating technology issues). No one response provides a complete answer, but putting all the bits and pieces together often solves the problem.
Not that using the internet as a big Help archive is anything new - I was just happy to find another source to search when I get a real stumper. But if nothing else, the Wikipedia Reference Desk Guidelines does make for interesting reading.