Information:
With Chbg you can set your background, but this program has a nifty "smart" mode, so even
images with unusual sizes will look good. You
won't have to mess with them.
You can also list more than one file, and Chbg will
change the backgrounds automatically and add a
customized delay.
There is a built-in graphical front-end, and you can
even use Chbg as an Xscreen saver hack.