Selectivizr : CSS3 pseudo-class and attribute selectors for IE 6-8
Woah.css : CSS Animation Library for eccentric web developers.
Animate.css : Animate.css is a bunch of cool, fun, and cross-browser animations for you to use in your projects.
320 and up : ‘320 and Up’ is a lightweight, easy to use and content first responsive web design boilerplate.
Flexibility : Flexibility is a polyfill for Flexible Box Layout Module Level 1. Use it to design beautiful, flexible layouts on the web without sacrificing the expe...
Animate On Scroll Library.
Small library to animate elements on your page as you scroll.