jquip : Smaller, Lighter, Faster, more modular jQuery - include only the parts you want! Don't use it, Don't include it.
stream.js : stream.js is a tiny stand-alone Javascript library that unlocks a new data structure for you: streams.
Timeline : Beautifully crafted timelines that are easy, and intuitive to use.
Wave.js : Audio visualizer library for javascript. Create dynamic animations that react to an audio file or audio stream.
hoverIntent jQuery Plug-in : hoverIntent is a plug-in that attempts to determine the user's intent... like a crystal ball, only with mouse movement! It is similar to jQuery's hove...
Sammy is a tiny javascript framework built on top of jQuery, It's RESTful Evented Javascript.