Wallpaper Cycler - NuonSoft WallpaperCycler is a powerfull utility to manage all your wallpapers and to automatically cycle between your wallpapers.
Muzei - Muzei is a live wallpaper that gently refreshes your home screen each day with famous works of art.
FCorp My Desktop - "ALL-IN-ONE" Desktop Related Tools.
Variety Wallpaper Changer - Variety is a wallpaper changer for Ubuntu which is featureful, yet slim and very easy to use.
John's Background Switcher - Switch backgrounds to trending imgur, reddit, tumblr threads
BioniX Desktop Wallpaper Changer - Free desktop wallpaper picture changer/desktop wallpaper manager software.