Soc.js
An easier way to create social icons
Simplate
A simple, but powerful, templating engine for JavaScript.
Readmore.js
A lightweight jQuery plugin for collapsing and expanding long blocks of text with "Read more" and "Close" links.
React Fb Image Grid
A beautifully featured image grid library for React which represents the images just like the facebook grid images with the count for extra as well
Moovie.js
Movie focused HTML5 Player
Mimosa
A lightning-fast, modular, next generation browser development tool.
Midi.js
Making life easy to create a MIDI-app on the web. Includes a library to program synesthesia into your app for memory recognition or for creating trippy effects. Convert soundfonts for Guitar, Bass, Drums, ect. into code that can be read by the browser. Supports multiple simultaneous instruments and perfect timing.
Maria
The MVC framework for JavaScript applications. The real MVC. The Smalltalk MVC. The Gang of Four MVC.
Java Script Load Image
JavaScript Load Image is a library to load images provided as File or Blob objects or via URL. It returns an optionally scaled and/or cropped HTML img or canvas element. It also provides a method to parse image meta data to extract Exif tags and thumbnails and to restore the complete image header after resizing.
J Query.black and White
Clientside grayscale images on any browser
Hook.js
Pull to refresh. For the web.
Highway
A fast, lightweight and simple Javascript routing library with no dependencies.
Gitdown
GitHub markdown preprocessor.
Elastislide
Elastislide is a responsive image carousel that will adapt fluidly in a layout. It is a jQuery plugin that can be laid out horizontally or vertically with a pre-defined minimum number of shown images
Componentjs
ComponentJS -- Powerful run-time Component System for structuring HTML5-based Rich Clients
Comic.js
Cartoon style drawing for HTML5 Canvas & Raphael.js & D3.js & SVG.js
Backgrid
Finally, an easily stylable semantic HTML data grid widget with a Javascript API that doesn't suck.