Nikola Mihaylov has written a game in Silverlight called Shock. This is not just a "fun project over the weekend" game. There are multiple game modes, music playlists, leaderboards, reflex tests, source code available and a whitepaper. Yes, Nikola is sharing his code along with a whitepaper entitled Anatomy of a Silverlight Game. 33 pages of the lessons he's learned while building his successful Shock game.
Enjoy and send him your feedback!