If you’re running Windows 7 (and you should be), you know that it has support for Themes, which are of course packs which define your desktop backgrounds, sounds, windows colors, etc.
Bing has a cool Theme which supports the RSS enclosure property, meaning that it will download new pictures from the web site continuously! So you’ll always get cool-looking, new images on your desktop background and you don’t have to do anything other than install it.
Just follow the directions here: http://www.blogsolute.com/2009/08/set-bing-images-desktop-wallpapers.html. Make sure you ‘save as’ the .Theme file and run it locally; if you don’t you won’t be prompted to allow the RSS enclosures to download!