Featherlight
Featherlight is a very lightweight jQuery lightbox plugin. It's simple yet flexible and easy to use. Featherlight has minimal css and uses no inline styles, everything is name-spaced, it's completely customizable via config object and offers image, ajax and iframe support out of the box. Featherlights small footprint weights about 4kB – in total.
Count Up.js
Animates a numerical value by counting to it
Amplify
AmplifyJS is a set of components for data management and application communication.
Shader School
A workshopper for GLSL shaders and graphics programming
Wysiwyg Editor
A flat designed jQuery WYSIWYG text editor based on HTML5, free only for non-commercial projects. For commercial applications you have to purchase a license from
jQuery.lazy
A lightweight, fast, feature-rich, powerful and highly configurable delayed content, image and background lazy loading plugin for jQuery & Zepto.
Superpowers Core
:octopus: Superpowers — Extensible HTML5 app for real-time collaborative projects
Sticky Kit
A jQuery plugin for creating smart sticky elements
Porthole
A proxy to safely communicate to cross-domain iframes in javascript
Mixitup
A CSS3 and jQuery Filter & Sort Plugin
Flow Type.js
Web typography at its finest: font-size and line-height based on element width.
FloraJS
FloraJS is a JavaScript framework for simulating natural systems in a web browser.
Tock
Timer Object/Class. Kickass!
Objgrep
Find strings inside complicated javascript objects
GLSL.js
A light Javascript & GLSL library for vizualisation and game purposes (2D or 3D).
Placeholder Shiv
Tiny polyfill for the placeholder form element attribute. Requires Prototype.js.
Money.js
money.js is a tiny (1kb) javascript currency conversion library, for web & nodeJS