Youtube and BL are pretty much the 2 websites I visit daily so this should be good though I think there are quite a few threads on this subject, but im not complaining.
Some topics I like to search for are:
Interviews with people important to me, most often music/fashion artists though really anyone, movie stars, sports stars, artists.
Im a surfer/bodyboarder so I love watching surf movies but you can find any sports on there and probably even most individual games of cricket/footy/soccer.
The newest/greatest music video's, also a great place to find new music and watch peoples interpretations of their favourite songs turned into video.
Dancing, I love watching Breakdancing/b-boying, C-walking, Shuffling, glowstik twirling, fire-twirling and peoples funny club/rave dances that theyve made up.
Drug documentaries/stories like intervention, speeches from the various psychedelic masters of previous years, Various shamanism doco's. Theres a lot worth watching.
You can pretty much type in any interesting word and find something worth watching, its a lot better than TV because it can be as educational as you want but if you just want mindless chillout session then you can get that too. I dont even know why I have cable TV because id say most shows on cable would be on youtube too.
Neurosoup