jQuery QR Code
qrcode generation standalone (doesn't depend on external services)
Comic.js
Cartoon style drawing for HTML5 Canvas & Raphael.js & D3.js & SVG.js
jCanvas
A jQuery plugin that makes the HTML5 canvas easy to work with.
J Query.black and White
Clientside grayscale images on any browser
P2.js
JavaScript 2D physics library
Cropper
A simple jQuery image cropping plugin.
Snap.svg
The JavaScript library for modern SVG graphics.
Html2canvas
Screenshots with JavaScript
Noisy
A jQuery plugin that adds random noise to the background of a given element.
Jcrop
Jcrop (official) - Image Cropping Plugin for jQuery
Liquidfun
2D physics engine for games
Paper.js
The Swiss Army Knife of Vector Graphics Scripting – Scriptographer ported to JavaScript and the browser, using HTML5 Canvas. Created by @juerglehni & @jonathanpuckey
Image Mapster
jQuery plugin for enhancing HTML Image maps
W Paint
jQuery Paint Plugin
P5.js
A JS client-side library for creating graphic and interactive experiences, based on the core principles of Processing. http://twitter.com/p5xjs —
Breathing Halftone
Images go whoa with lots of floaty dots
jQuery Focuspoint
jQuery plugin for 'responsive cropping'. Dynamically crop images to fill available space without cutting out the image's subject. Great for full-screen images.