SPF : A lightweight JS framework for fast navigation and page updates from YouTube
Sammy.js : Sammy is a tiny javascript framework built on top of jQuery, It's RESTful Evented Javascript.
InstantClick : InstantClick is a JavaScript library that dramatically speeds up your website, making navigation effectively instant in most cases.
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...
TraceKit : Not all browsers support stack traces on error objects, but TraceKit squeezes out as much useful information as possible and normalizes it.
Smaller, Lighter, Faster, more modular jQuery - include only the parts you want! Don't use it, Don't include it.