WS-Sudoku has two facets:
WS-Sudoku is my implementation of the Sudoku game that allows multi-player game. An individual can start a game in service mode, to which other players can connect to and solve the game together.
The game uses WSDualHttpBinding and uses callback contracts, in a publisher-subscriber model, for notifying all connected players about the moves made by other players. As players join or exit the game, the notifications are sent in real time to other players in the game. It has been built using WCF November CTP. You would require the following components to be installed on your machine:
Below is a screen shot of the game:

Finally, it can be installed using ClickOnce so that it will auto-update itself when updated for more features.
To download as a zipped archive, or install it over-the-web, visit http://www.wintoolzone.com/showpage.aspx?url=http://www.wintoolzone.com/clickonce/ws-sudoku
Technorati : Sudoku, WCF, WSDualHttpBinding, WinFX, Windows Communication Foundation
Del.icio.us : Sudoku, WCF, WSDualHttpBinding, WinFX, Windows Communication Foundation
43 Things : Sudoku, WCF, WSDualHttpBinding, WinFX, Windows Communication Foundation