For some months I've been playing around with HTML 5's Canvas element because I was curious about it, especially after seeing it run Flash. I hacked at it for a while then realized I had produced an Asteroids game.

Tower Game is a HTML5 canvas tower building game using javascript. MIT licensed and has some option to customize.

Planck.js is a 2D JavaScript physics engine for cross-platform HTML5 game development.

Features:

• Taking advantage of Box2D's efforts and achievements
• Developing readable and maintainable JavaScript code
• Optimizing the library for web and mobile platforms
• Providing a JavaScript-friendly API