We covered the app Ffffound by our own RogueCode a few weeks ago. The app pulls down user created pop-art from the site of the same name, Ffffound.com, but in a really svelte manner--great transitions, minimalist design and the ability to save to your device for use as wallpaper or sharing with others.
The app was recently updated to fix issues with saving and some device memory problems, letting it work fully as it should. It's a nifty little app that even has a Live Tile that shows the latest image, giving your Start screen a little pizzazz.
For $0.99 the app was a great deal, in our opinion, but now for the next week you can pick it up for free--no strings attached. That's a great offer for a very well deigned app, so might as well take advantage while you can.
Check out the video review after the break and grab the app here in the Marketplace.