Big.js
A small, fast JavaScript library for arbitrary-precision decimal arithmetic.
Placeholder Shiv
Tiny polyfill for the placeholder form element attribute. Requires Prototype.js.
Classing Js
Brings the world of classical OOP to javascript
Char Funk
a Unicode character utility for JavaScript
Core Lib
A port of the Ruby 1.9.3 corelib to coffeescript/javascript/node that conforms to rubyspec.org.
CSS3 Pie
A behavior for Internet Explorer allowing it to recognize and render various CSS3 box decoration properties
Klass
a utility for creating expressive classes in JavaScript
Ratio.js
Rational numbers for Javascript
Object.observe
Object.observe polyfill/shim trying to be compliant
Taggd
A tool to show and add tags to images
Args.js
Create javascript functions with optional, default, grouped and named parameters.
Css3 Finalize
Tired of adding prefix for each broswer when it comes to the new css3 attributes?
Selectivizr
Selectivizr is a JavaScript utility that emulates CSS3 pseudo-classes and attribute selectors in Internet Explorer 6-8.
Length.js
📏 JavaScript library for length units conversion.
Respond
A fast & lightweight polyfill for min/max-width CSS3 Media Queries (for IE 6-8, and more)
Yepnope.js
An Asynchronous Conditional Resource Loader
Numeral
A javascript library for formatting and manipulating numbers.