WebWallpaper Downloader is a free to use program which allows you to download images from random wallpaper at Interfacelift.com, Photo of the Day from National Geographic and NASA Image of the Day. It will set the download images as desktop background automatically without any effort from your end, It will automatically download wallpapers as per your desktop resolution which I found very intelligent.
It does not a visual interface, when ever you click the desktop shortcut of this program it will download a new wallpaper and set it as desktop background. It will download all the wallpapers in the folder on the path C:\Program Files\Webwallpaper\wallpapers – you can copy these wallpaper later on.
Some other free wallpaper downloader we have written about are Wallpaper Juggler, Wallpaper Downloader and NatGeo Wallpaper Downloader and we also featured a cool utility for downloading wallpapers for free on iPhone