Selectivizr : CSS3 pseudo-class and attribute selectors for IE 6-8
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...
320 and up : ‘320 and Up’ is a lightweight, easy to use and content first responsive web design boilerplate.
Animate.css : Animate.css is a bunch of cool, fun, and cross-browser animations for you to use in your projects.
Autoprefixer : PostCSS plugin to parse CSS and add vendor prefixes to CSS rules using values from Can I Use.
Animate On Scroll Library.
Small library to animate elements on your page as you scroll.