YouTube is not just a website that allows video makers to share their programs with the world but as teachers we can find serveral very useful video clips that we can use in our classes, legally, but just linking to them on this site or using the Embedded HTML codes available.
You can find the famous Herding Cats clip, 5 minute University, Clips from the Movie “Ferrus Beuller’s Day Off” and many move.
You can also set up an account and create a list of favourites. Check it out at http://www.youtube.com/
And since Google just bought them, you should see a convergence between Google Video and YouTube.
I also like to use the funny clips as reward easter eggs in my online classes but you need to watch out for offensive materials here.