When it comes to automatically changing wallpapers for your Windows desktop, there are many freeware app including the recently released Bing desktop. My Daily Wallpaper is yet another useful tool for desktop wallpapers which can automatically change the desktop wallpaper by download a new one. The good thing about this app is that it download high resolution wallpapers from Deviantart. There are pretty good options to filter out wallpapers while downloading them.
As you can see from the image above, you can select the categories from which you want to download. You can download from over 80.000 hi-quality wallpapers available in 18 categories. Another good feature is that the app can filter wallpapers based on the screen resolution, so that you can get the perfect wallpaper for your desktop.
There is also a random wallpaper option where the app will download some random wallpapers and you can manually set them as desktop wallpaper.
Overall, a very good app especially considering that Deviantart has large collection of awesome wallpapers.