a 2D rigid body physics engine for the web
Blend4Web is a tool for interactive 3D visualization on the Internet
Framework for HTML5 Canvas oriented 2D video games
GameJs is a thin library on top of the HTML canvas element. In addition to the drawing functions it has a set of generally helpful modules for game development.
Turbulenz is a modular 3D and 2D game framework for making HTML5 powered games for browsers and mobile devices.
Panda.js HTML5 game engine
A Joyful 2D HTML5 Game Engine.
html5 game engine optimized for rapid development