Bacon.js
FRP (functional reactive programming) library for Javascript
Almond
A minimal AMD API implementation for use after optimized builds
Aja.js
Ajax without XML : Asynchronous JavaScript and JavaScript/JSON(P)
Jquery.payment
A general purpose library for building credit card forms, validating inputs and formatting numbers.
Retina.js
JavaScript and LESS helpers for rendering high-resolution image variants
Imagesloaded
JavaScript is all like "You images done yet or what?"
Twig.js
JS implementation of the Twig Templating Language
Machina.js
js ex machina - finite state machines in JavaScript
Javascript State Machine
A finite state machine javascript micro framework
FullCalendar
Full-sized drag & drop event calendar (jQuery plugin)
Forerunner Db
A JavaScript database with mongo-like query language, data-binding support, runs in the browser as a client-side DB or on the server via Node.js!
C3
A D3-based reusable chart library
Angular Strap
AngularJS 1.2+ native directives for Bootstrap 3.
Toolbar
A tooltip style toolbar jQuery plugin
Keydrown
A JavaScript key state handler for web apps
Ethvtx
🌀Ethereum-Ready & Framework-Agnostic Redux Store Configuration
Eqcss
EQCSS is a plugin that introduces Element Queries, Scoped CSS, a Parent selector, and responsive JavaScript to all browsers IE8 and up