Phaser is a light-weight 2D game framework for making HTML5 games for desktop and mobile browsers
Egret is a brand new open mobile game and application engine which allows you to quickly build mobile games and apps on Android,iOS and Windows.
Super fast HTML 5 2D rendering engine that uses webGL with canvas fallback
a 2D rigid body physics engine for the web
JSIso - An HTML5 Canvas Tile Engine
Kiwi.js is a blazingly fast mobile & desktop browser based HTML5 game framework. It uses CocoonJS for publishing to the AppStore.
A virtual joystick for touch capable interfaces.
:octopus: Superpowers — Extensible HTML5 app for real-time collaborative projects
A Joyful 2D HTML5 Game Engine.
Turbulenz is a modular 3D and 2D game framework for making HTML5 powered games for browsers and mobile devices.