SPF : A lightweight JS framework for fast navigation and page updates from YouTube
InstantClick : InstantClick is a JavaScript library that dramatically speeds up your website, making navigation effectively instant in most cases.
Sammy.js : Sammy is a tiny javascript framework built on top of jQuery, It's RESTful Evented Javascript.
Rickshaw : Rickshaw is a JavaScript toolkit for creating interactive time series graphs.
Prepack : Prepack is a tool that optimizes JavaScript source code: Computations that can be done at compile-time instead of run-time get eliminated. Prepack rep...
Smaller, Lighter, Faster, more modular jQuery - include only the parts you want! Don't use it, Don't include it.