Express
Sinatra inspired web development framework for node.js -- insanely fast, flexible, and simple
Durandal
A cross-device, cross-platform client framework written in JavaScript and designed to make building Single Page Applications (SPAs) easy to create and maintain.
PubNub
PubNub makes Real-time Real Easy with a Simple Communications API. Two Functions: Send/Receive (Publish/Subscribe). We provide a web-service API for businesses to build scalable Data Push communication apps on Mobile, Tablet and Web. Bidirectional JSON.
Joosy
Joosy is a browser applications framework. That is based on Rails, CoffeeScript and love.
Maria
The MVC framework for JavaScript applications. The real MVC. The Smalltalk MVC. The Gang of Four MVC.
Layr
Dramatically simplify full‑stack development
Black Hole.js
Renders black hole gravitational lensing effects in an image canvas using WebGL, glfx.js, and numeric.js
Knockout
Knockout makes it easier to create rich, responsive UIs with JavaScript
Batman
Fighting Crime and Kicking Apps
Montage
Core framework: Montage simplifies the development of rich HTML5 applications by providing modular components, real-time two-way data binding, CommonJS dependency management, and many more conveniences. Join us on irc.freenode.net#montage or https://groups.google.com/d/forum/montagejs
Thinkjs
Use full ES2015+ features to develop Node.js applications, Support TypeScript.
Flux
Application Architecture for Building User Interfaces
Angular Meteor
Combining the simplicity and power of AngularJS and Meteor
Blizzard.js
A promise-based Node.JS library for the Blizzard Battle.net Community Platform API
Simplecart
A simple javascript shopping cart that easily integrates with your current website.
Wee
Blueprint for modern web development