JS Plumb
jQuery/MooTools/YUI3 Javascript library that lets you connect parts of your UI together.
Izi Modal
Elegant, responsive, flexible and lightweight modal plugin with jQuery.
P2.js
JavaScript 2D physics library
Parallel.js
Parallel.js is a tiny library for multi-core processing in Javascript.
Highland
High-level streams library for Node.js and the browser
Backbone localStorage
A localStorage adapter for Backbone.js
jQuery.panzoom
A jQuery plugin for panning and zooming elements using CSS3.
Basket.js
A script and resource loader for caching & loading files with localStorage
Packery
bin-packing layout library
Lettering.js
A lightweight, easy to use Javascript <span> injector for radical Web Typography
Metismenu
A jQuery menu plugin
Imager.js
Responsive images while we wait for srcset to finish cooking
Tooltipster
A jQuery tooltip plugin
Datejs
Datejs is an open-source JavaScript Date Library.
Bricks.js
A blazing fast masonry layout generator for fixed width elements.
Sammy
Sammy is a tiny javascript framework built on top of jQuery, It's RESTful Evented Javascript.
Swing
A swipeable cards interface. The swipe-left/swipe-right for yes/no input. As seen in apps like Jelly and Tinder.