I actually didn't get a chance to make a post about this earlier, but wanted to mention we handled development of the Captain America wallpaper that's currently on the Market. We were approached by Disney Interactive to make something Android-specific to help promote their game (published under the Marvel banner), and though we had rather a lot going on at the time I was really excited to make something for them.
After some initial discussion we decided to keep it reasonably simple, and focus on a nice looking treatment of the shield, with some additional motion to help keep things active. The artwork is based on the original film shield and turned out very well, I think, and you get bullets bouncing off as you interact with it.
Hopefully everyone likes the result!