How to change my computer background to an animated picture?

I don’t think it can be done, and if so, why doing that? It will affects the computer’s performance.

On Windows 7 I don’t find a way to do that, but you can make a replacement of the background picture every X minutes, so if you have 5 picture that every one of them has a slight change in motion, it may look like your bacground is animated, but it just few picture or slideshow change after a while.

Animated desktop wallpapers aren’t usually supported by the OS. You need a third party product.

Google’s first suggestion for Windows users is Dreamscapes.

And I just found Vital Desktops, which is free.

Yes, I guess third party tools would be needed.

This is not full fledged animation, but if you are interested in a dynamic clock as wallpaper, you can check out the following site—http://www.vladstudio.com/wallpaperclock/

Take a look at My Living Desktop for OSX. It may do what you want.

http://www.youtube.com/watch?v=tOoviwRTcmY

If you can get it to run as a screensaver you can run this command in the Terminal to run it as your desktop.

/System/Library/Frameworks/ScreenSaver.framework/Resources/ScreenSaverEngine.app/Contents/MacOS/ScreenSaverEngine -background

@johnpowell Woah! How does this work? Can you select a screensaver from the System Prefs to show on the background?

@Vortico :: Whatever screensaver is selected in sys prefs will run as a desktop picture. I like Flurry.

@johnpowell : Woah, neato.

@johnpowell, it’s not as CPU intensive as I thought, but still a lot. The iTunes Visualizer isn’t as bad, and makes for a great animated background.