I've just put out the first attempt at a StackApps application. StackBook helps you let your Online Community (right now only Facebook) friends know what you're doing on Stack Overflow.

In v0.1 the application will update your Facebook stream when you ask a question on StackOverflow.

Check it out at http://stackbook.mourfield.com/ . Let me know what you think and what I can do to make it better!