Cyber-Ds Wallpaper Shifter can randomize your wallpaper on startup, when you login to Windows and picks a random wallpaper from your list. Depending on the wallpaper width and height, it can automagically scale it for you to fit your desktop without deforming its proportions. It does not remain running in the background so no system resources are used.

The license of this software is Freeware, you can free download and free use this wallpaper tool software.