This is a Ruby on Rails app implementing a chinese poker game. User accounts are authenticated with OpenID. It is also possible to embed the app as a Facebook app, or using OpenSocial.
You create a match inviting one to three other friends. Each player is notified about the match, and allowed to set his hand. When all players have finished setting their hands, the match is scored. Scores are accumulated across matches between each pair of players.
The app is based on Ruby on Rails, and uses the YUI css/javascript library.