Walyk Wallpaper Changer - Walyk Wallpaper Changer allow you to change your wallpapers automatically or manually.
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.
Muzei - Muzei is a live wallpaper that gently refreshes your home screen each day with famous works of art.
Desktopnova - This application brings a little variety onto your desktop!
FCorp My Desktop - "ALL-IN-ONE" Desktop Related Tools.