I first saw this through BoingBoing, and have seen it posted on a lot of blogs, but not to any of the ones I check out on film. A professor at Kansas State University, Michael Wesch created it, and it's a brilliant videoexplanation of hypertext, the web, web 2.0 and why this stuff matters. We made it mandatory viewing for the staff here at Renew Media, and I highly recommend it for anyone who cares about where the net is taking us, and what it means for video, copyright, politics, etc. Enough said, cause this man does it better than I can. Link.
I don't know why, but the start image is a bit screwy - the video does seem to play though.