Replace jQuery or MooTools with a <4kB Library
let's you know when the dom is ready
A lightweight, fast, feature-rich, powerful and highly configurable delayed content, image and background lazy loading plugin for jQuery & Zepto.
A utility library for observing visibility changes of DOM elements.
NodeList implementation/library - Use the Native DOM APIs as easily as jQuery
Injects CSS into the document (it's a perfectly legal procedure)
Tapestry 5 jQuery integration. Fully replace Prototype and Scriptaculous with jQuery with as less as possible compatibility issues
bind.js - simple two way data binding to HTML and callbacks
Exit popup easely. Detects if the mouse of a user leaves the viewport borders of your website
MagJS - Modular Application Glue
Gets the dimensions of the Viewport and beyond.
A tiny tool for easily loading html fragments and templates
Sane DOM Generation
A modern, lightweight browser library using ES5 natives