Auto Numeric
autoNumeric is a jQuery plugin that automatically formats currency (money) and numbers as you type on form inputs. It supports most International numeric formats and currency signs including those used in Europe, North and South America, Asia and India (lakhs**).
CSS Parent Selector
CSS4 parent selector based on jQuery
Svgeezy
Allows for automatic Image fallbacks for browsers that can't handle SVGs
Augment.js
Modern JavaScript in your IE
Css3 Finalize
Tired of adding prefix for each broswer when it comes to the new css3 attributes?
Char Funk
a Unicode character utility for JavaScript
Es6 Shim
ECMAScript 6 (Harmony) compatibility shims for legacy JavaScript engines
Args.js
Create javascript functions with optional, default, grouped and named parameters.
Typecast.js
Typecast.js :: Solving the simple problems
ES5 Shims
ECMAScript 5 compatibility shims for legacy JavaScript engines
Core Lib
A port of the Ruby 1.9.3 corelib to coffeescript/javascript/node that conforms to rubyspec.org.
Ratio.js
Rational numbers for Javascript
Object.observe
Object.observe polyfill/shim trying to be compliant
Poly
Small, fast, awesome. The only ES5-ish set of polyfills (shims) you can mix-and-match because they're individual AMD modules.
Big.js
A small, fast JavaScript library for arbitrary-precision decimal arithmetic.
Length.js
📏 JavaScript library for length units conversion.
Datejs
Datejs is an open-source JavaScript Date Library.