http://www.youtube.com/
I don't know if anyone has heard of this website yet, but my best friend's brother and a couple college friends started it a few months ago and it has really started to take off. Basically, it's a free site to share videos and watch videos that other people have made. It's a really interesting site and obviously a lot of people really like it so I thought I'd mention it here to see if people used it or what they thought/think about it; and if you havn't been there, check it out.
Also, this month they are giving an iPod nano away in a drawing every day, if that grabs anyone's attention. You get one entry when you sign up and another one for each friend you invite.