reference http://www.techsupportalert.com/content/best-free-wallpaper-changer.htm
John’s Background Switcher
I can’t stand plain, boring backgrounds. John’s Background Switcher (or JBS for short) periodically changes the background image on your Windows computer to something awesome. Support for change wallpaper on primary or secondary monitor only every x time! (where windows cant!)
You can specify which pictures to choose from: -Folders containing pictures on your computer such as ‘My Pictures’ or Dropbox! -Any Media RSS feed or Flickr / Facebook / Instagram / Vladstudio / 500px / Phanfare / smugmug / Picasa / Google Image Search / Pixabay / Last.fm
http://johnsad.ventures/software/backgroundswitcher/windows/
Dual Monitor Tools Is a software package for Windows users with dual or multiple monitor setups. Each tool is independent so you only need to install or run what you want.
http://dualmonitortool.sourceforge.net/
Walyk Wallpaper Changer Manage your Wallpaper collections. http://www.walyk.com/
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