1)   TyphoonWallpaper 1.0
Choose any picture as your desktop wallpaper. Provides access to our huge library of free super hi-res wallpaper images. Features include auto-cycling of wallpaper images, wallpaper special effects, and support for multiple monitors.

 2)   EvJO Wallpaper Changer 1.4
"EvJO Wallpaper Changer" is a wallpaper manager that can change your background images at every startup, once a day or at regular time intervals. It features JPEG, PNG, GIF and BMP support.