Here is the template and tutorial for creating a great YouTube background.

http://www.askmrvideo.com/yt.pxd <-- (right click and Save As)

http://www.askmrvideo.com/yt.zip <-- (same in zip format - IE users right click and Save As)

http://screencast.com/t/gxRQCV11v <-- Tutorial Part 1, Customizing using Pixlr.com

http://screencast.com/t/Z15Wk0RZ <-- Tutorial Part 2, installing on YouTube