Dun, Dun, Daaah!
If you havn't already,
Check it out!
This first one has an interesting wallpaper. Sorry about that, This guy is a little crude. I wanted another vid but the person who posted it pulled it. It is very well done otherwise for demonstrating the uses and effects of the Ubuntu Linux Desktop.
This one is nice as it shows some of the other effects as well as the ability to not be hindered by 3D video play.
Not posted but available: some videos showing Windows XP being run inside the Linux desktop.
I am a User Interface Design Major so this sort of thing is of personal interest to me.
Linux is Free though, so if you or someone you know needs an OS and Feel uncomfortable about paying for Windows, or Vista or whatever, and don't want to pirate a copy, this is a REally good alternative.