Play by yourself in a web browser like Chrome or Safari. The game simulates the other players. Runs best on a desktop computer or laptop. Also tries to adapt to an iPad or tablet. Players can make mistakes and can leave and join. You can cheat and get the game to correctly mark your board. There is no limit to the number of players (try 300,000). You can adjust the speed of the game and most sizes. The game can play for you. You can hear the caller reading out the numbers and the players...
Dragon Go Server is a web-based server for playing go (a.k.a baduk, weichi and igo). It's intended as a replacement for play-by-email, where the server keeps tracks of the moves. Tools used are php and mysql.
NetRisk GWT allows anyone to play a full game of Risk with up to 8 players from any Javascript enabled browser. Bases on the code of NetRisk 2.0 (https://sourceforge.net/projects/netrisk/) Demo: http://www.netrisk-online.de/
A PHP Web Application that you can install on your own web server. It allows you to play chess with other users across the internet or sitting at the same screen. It only permits valid moves and can automatically detect check and checkmate status.
netjatafl is a hnefatafl server and client system, allowing tafl players to join in networked games of tafl. Using a standard network protocol, new clients can be written for any platform. Clients in C++ and PHP/Javascript are included.
Javascript platform for tile map based single/multiplayer games with both off-line and server-based play modes. Try it out right away at http://tilescape.hg.sf.net/hgweb/tilescape/raw-file/tip/js/game.html
Chessd is a chess XMPP based server. It uses a web interface and a BOSH server, that runs between interface and the chess server. Visit http://xadrezlivre.c3sl.ufpr.br to see it in action.