If there’s one thing that can compete with lightboxes for “world’s most done-to-death jQuery plugin,” it’s carousels. Everything Mat came across was using pixel values and not percentages—meaning nothing that could be used on a responsive/flexible layout. So Mat built one.
The creator of this plugin has done a lot of awesome responsive design things especially around responsive images (and in this case the little cart that takes them around the page).
A lightweight, easy-to-use jQuery plugin for fluid width video embeds.
Imgsizer.js cycles through your document, swaps out the images for a transparent GIF, and applies the AlphaImageLoader property to each one.
Enquire.js is a lightweight, pure JavaScript library for handling media queries. It is less than 1kb when GZIP'd and minified, and has absolutely no dependencies. Yup, you read that right - no dependencies, not even jQuery! The most you will have to do is provide a matchMedia polyfill if you wish to support browsers without a native implementation.
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