Ember.js : A JavaScript framework for creating ambitious web applications
Backbone.js : Backbone.js gives structure to web applications by providing models with key-value binding and custom events, collections with a rich API of enumerabl...
script.aculo.us : script.aculo.us provides you with
easy-to-use, cross-browser user
interface JavaScript libraries to make
your web sites and web applications fly.
MooTools : MooTools is a compact, modular, Object-Oriented JavaScript framework designed for the intermediate to advanced JavaScript developer. It allows you to ...
The Dojo Toolkit : Dojo saves you time and scales with your development process, using web standards as its platform. It’s the toolkit experienced developers turn to for...