video.google.com - Google is now indexing transcripts on TV shows. The search results include images from the show (no video yet). So far it looks like it doesn't actually have full transcripts. For example, last night's Everwood only has two paragraphs of text. This is still in beta, though. Yahoo has a video search, but it seems more like images.google.com. It just searches within regular web pages for video clips. Blinkx.tv is another option, and it also searches for video, not for text within television programs. If I were searching for a video clip, I would use one of the latter two, but if I were looking for some infomation that I think was on TV, I would go with Google.

(via CNET News.com)