GRandomWallpaper is a simple utility that lets you randomize the wallpaper images
on your GNOME (Nautilus) desktop.
It selects a random image from a pool of many images (a directory), it keeps track of how many times an image has been displayed, and those that have not been displayed as often are more likely to get picked. It is customizable and can be used to randomly select a wallpaper every N seconds, or to do it only once. It can also keep track of a list of "banned" images that will never be displayed.