Websites of Knowledge?
AvantLegion asks: "Every now and then, I stumble upon a website that is just a veritable tome of knowledge - be it of a certain theme (like Snopes.com) or more general information (Everything2.com). Free documentation databases are invaluable, but rarely seem to come up very early in Google searches. What websites out there do you consider to be indispensable sources of knowledge? (save the obvious Slashdot jokes). Where do you look up information besides combing through search engine results?"
Most of the examples I've seen in the comments so far are full of information. It is up to you to turn that information into knowledge. I'd say that websites containing actual knowledge as opposed to information are few if not nonexistent.
Sorry to be so pedantic, but the speaker at my college graduation said something along the lines of, "seek knowledge, not information" and it's the one thing from his speech that has stuck with me. Use information to gain knowledge, and use knowledge to gain wisdom. It is only through the power of the willing human mind that each transforms into the next.
But anyway, back to your regularly scheduled links full of cool information...