EnhanceJS : EnhanceJS is a new Javascript framework designed to improve the application of Progressive Enhancement by first testing browser capabilities for key J...
xui.js : A super micro tiny DOM library for authoring HTML5 mobile web applications.
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 ...
Band.js : An interface for the Web Audio API that supports rhythms, multiple instruments, repeating sections, and complex time signatures.
Not all browsers support stack traces on error objects, but TraceKit squeezes out as much useful information as possible and normalizes it.