jsPDF : A library to generate PDFs in client-side JavaScript.
Zero Clipboard : The Zero Clipboard library provides an easy way to copy text to the clipboard using an invisible Adobe Flash movie, and a JavaScript interface. The "Z...
Ember.js : A JavaScript framework for creating ambitious web applications
Crafty : JavaScript Game Engine, HTML5 Game Engine
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.
JavaScript Libraries for adding offline support to web apps.