Phaser is a light-weight 2D game framework for making HTML5 games for desktop and mobile browsers
Blend4Web is a tool for interactive 3D visualization on the Internet
phina.js is game library
a 2D rigid body physics engine for the web
Super fast HTML 5 2D rendering engine that uses webGL with canvas fallback
A Joyful 2D HTML5 Game Engine.
JSIso - An HTML5 Canvas Tile Engine
html5 game engine optimized for rapid development
A virtual joystick for touch capable interfaces.