John's Background Switcher - Switch backgrounds to trending imgur, reddit, tumblr threads
Bulk Image Downloader - With Bulk Image Downloader you can download full sized images from almost any web gallery.
Variety Wallpaper Changer - Variety is a wallpaper changer for Ubuntu which is featureful, yet slim and very easy to use.
Extreme Picture Finder - Extreme Picture Finder is a powerful batch image downloader.
Wallpaper Cycler - NuonSoft WallpaperCycler is a powerfull utility to manage all your wallpapers and to automatically cycle between your wallpapers.
Image Downloader - Chrome extension to download images from websites.