A tip for today's starter: ReviveTube. This site lets you watch videos that YouTube has pulled from its public archive because of censorship complaints.
It seems to work by accessing the Flash files directly from YouTube's servers since when it "deletes" a video, really all that YouTube does is just deny access to the page it's on. The files are still cached an accessible, provided you know how to get at them. Luckily, ReviveTube does.