Ratchet
Prototype iPhone apps with simple HTML, CSS, and JS components.
Crypto Js
JavaScript library of crypto standards.
Dc.js
Multi-Dimensional charting built to work natively with crossfilter rendered with d3.js
Zxcvbn
zxcvbn, named after a crappy password, is a JavaScript password strength estimation library. Use it to implement a custom strength bar on a signup form near you!
Vivus
JavaScript library to make drawing animation on SVG
Bootstrap Datetimepicker
Date/time picker widget based on twitter bootstrap
Page.js
Micro client-side router inspired by the Express router (~1200 bytes)
Pdfmake
Client/server side PDF printing in pure JavaScript
Matter JS
a 2D rigid body physics engine for the web
Sigma
An open-source lightweight JavaScript graph drawing library
Aurelia Framework
The aurelia framework brings together all the required core aurelia libraries into a ready-to-go application-building platform.
Chai
BDD / TDD assertion framework for node.js and the browser that can be paired with any testing framework.
Onsen Ui
Custom Elements-Based HTML5 UI Framework for Building Your Mobile Front End
Loaders.css
Delightful, performance-focused pure css loading animations.
Easel JS
The Easel Javascript library provides a full, hierarchical display list, a core interaction model, and helper classes to make working with the HTML5 Canvas element much easier.
UA Parser
Lightweight JavaScript-based User-Agent string parser. Supports browser & node.js environment. Also available as jQuery plugin.
Wow
Reveal CSS animation as you scroll down a page