Extending the reach of your 2D XNA game to the web
I'm currently working on an exciting pet project. The idea is to allow you to compile an XNA 2D game as a Silverlight application with no code changes. I currently have my Dr. Popper game for Xbox Live Community Games running successfully in Silverlight with no code changes, so it is possible. There are some limitations right now, like no render targets or pixel shader support, no direct manipulation of Texture2D data, and no sprite fonts that load from a bitmap. Some of these features will be available eventually, some with the help of new features coming in Silverlight 3.
I'm looking for more games that I can try to get running to work out some of the kinks in the library, so if you're interested please let me know. It also may turn into a new revenue stream for your game:
http://www.bluerosegames.com/silverlight-games-101/post/Got-a-Silverlight-Game-Want-to-make-some-money.aspx
or you could put an online version out to promote your Xbox Live Community Game.