John's Background Switcher enables you to automatically switch your desktop wallpaper every X hours. You can select individual images to be used or rotate through images in a folder on your PC or downloaded from various images sites including Flickr, SmugMug, Picasa, Facebook, Yahoo! and others. The program can display images in full-screen mode or as image collage in different styles. A variety of settings allow you to customize the behavior (image scaling, background effects, size etc.), exclude images from being shown and more. Other features include support for multiple monitors, RSS feeds, optional calendar display, background effects and more.