Gremlins.js
Monkey testing library for web apps and Node.js
Enquire.js
Awesome Media Queries in JavaScript
Adapt
Adapt.js serves CSS based on screen width.
jQuery jKit
A very easy to use, cross platform, jQuery based UI toolkit, that's still small in size, has the features you need, and doesn't get in your way of doing things!
Vue Trend Chart
Simple trend charts for Vue.js
Shine.js
A library for pretty shadows.
Nested
Gap free multi column grid
Keydrown
A JavaScript key state handler for web apps
Jmpress.js
A jQuery plugin to build a website on the infinite canvas
Delorean
An Agnostic, Complete Flux Architecture Framework
Datalist Polyfill
Minimal and dependency-free vanilla JavaScript polyfill for the awesome datalist-functionality
Sprintf.js
sprintf.js is a complete open source JavaScript sprintf implementation.
Skel
A lightweight responsive framework for the www
Request
Simplified HTTP request client.
Knockout
Knockout makes it easier to create rich, responsive UIs with JavaScript
Stellar.js
Stellar.js - Parallax scrolling made easy
Node Browserify
browser-side require() the node.js way