REMLAB is a fully functional cross-platform web-based Battlemech designer for the tactical board game Battletech. REMLAB is built entirely on HTML, PHP, and JavaScript with Ajax functionality.
Hundiyas is an open source "Battleship" alike game totally written in DHTML (JavaScript, CSS and HTML) that uses mouse. This cross-platform and cross-browser game was tested under BeOS, Linux, *BSD, Windows and others.
The Freya Game Engine is a crossplatform Java API for writing multiplayer turn based games. The engine produces XML turn descriptions based on XML command files and XML data dictionaries.