You probably know about Hulu, the website where you can watch TV episodes and movies, and you might watch clips on news websites and then hop over to YouTube to catch the latest viral video, but now you can search videos from across the web and see them in one place with VideoSurf.
According to their About page, VideoSurf can search visual images, not just text, so you can get right to a scene or segment. They include Yahoo, ESPN, MySpace, CNN, and more to bring you "over 50 billion visual moments." If you want to share a video, it's possible to share just a portion instead of the entire thing.
If you use Firefox, there's an extension over at Mozilla (see the link at the bottom of VideoSurf's homepage) that lets you preview any video before watching the whole thing. Pretty cool.
Check out the FAQ for some how-tos. It's a nifty tool for finding videos from many sources, all in one search.