Canvas

JavaScript Canvas Drawing Library in Browser : Artisan JS
Artisan JS is a JavaScript Canvas Library that aims to make in-browser drawing very easy. It’s a standalone, that doesn’t require an JavaScript frameworks. This javascript canvas offers simpler and shorter-to-write functions for creating and styling objects.

HTML5 Canvas Utility Library : Gury
Gury is a JavaScript library designed to aid in the creation of HTML5 Canvas applications by providing an easy-to-use chain based interface.

HTML5 Canvas For Image Manipulation : CamanJS
CamanJS is Javacript library for image manipulation using the HTML5 canvas and Javascript. It’s a combination of a simple-to-use interface with advanced and efficient image/canvas editing techniques. It is also completely library independent and can be safely used next to jQuery, YUI, Scriptaculous, MooTools, etc.