FCorp My Desktop - "ALL-IN-ONE" Desktop Related Tools.
Muzei - Muzei is a live wallpaper that gently refreshes your home screen each day with famous works of art.
John's Background Switcher - Switch backgrounds to trending imgur, reddit, tumblr threads
Variety Wallpaper Changer - Variety is a wallpaper changer for Ubuntu which is featureful, yet slim and very easy to use.
Wallperizer - Wallperizer is a desktop wallpaper changer.
CommandLine Wallpaper Changer - Change Wallpaper From little Command Line Application