Crafty : JavaScript Game Engine, HTML5 Game Engine
ActiveJS : ActiveJS is a JavaScript application framework that provides local and REST based data modeling and pure DOM view construction with back button and hi...
Workbox : JavaScript Libraries for adding offline support to web apps.
The HTML5 Shiv : The HTML5 Shiv enables use of HTML5 sectioning elements in legacy Internet Explorer and provides basic HTML5 styling for Internet Explorer 6-9, Safari...
RequireJS : RequireJS is a JavaScript file and module loader. It is optimized for in-browser use, but it can be used in other JavaScript environments, like Rhino ...
Namespace.js is a small javascript script which provide namespacing utilities. It is framework independent. It also allows you to remotely include files.