Cropper.js is a powerful javascript image cropper with cross-browser support and much more features. Also there is a jQuery plugin wrapper for Cropper.js
Matter.js is a 2D rigid body physics engine for the web written in JavaScript.
Rangy is a cross-browser JavaScript range and selection library.
Rangy also comes with optional modules, each of which comes in a separate .js file.
Fine Uploader is a multiple file upload plugin with image previews, drag and drop, progress bars. S3 and Azure support, image scaling, form support, chunking, resume, pause, and tons of other features.
Validatr is a jQuery plugin that relies on using modern HTML5 input attributes to perform validation.
Store.js is a localStorage wrapper for all browsers without using cookies or flash. Uses localStorage, globalStorage, and userData behavior under the hood.
KUTE.js is a minimal native Javascript animation engine with jQuery plugin and with most essential features for web developers, designers and animators, delivering easy to use methods to set up high performance, cross-browser animations. The focus is flexibility, performance and size.
Push.js is a compact, cross-browser solution for using the JavaScript Notifications API.
megamenu.js is a responsive, cross-browser, jQuery mega menu.
Features
Zebra_Transform is a lightweight, cross-browser (with IE6 support) jQuery plugin for replacing checkboxes, radio buttons and select boxes.
Zebra_Datepicker is a lightweight, highly configurable, cross-browser jQuery date picker plugin.
This plugin will automatically add a calendar icon to the indicated input fields which, when clicked, will open the attached datepicker
Viewer is a simple jQuery image viewing plugin.
Features
Air Datepicker is a lightweight cross-browser jQuery datepicker, built with es5 and css-flexbox. Works in all modern browsers.
A lightweight jQuery WYSIWYG text editor based on HTML5 technology. Cross browser, with mobile support, high performance and Retina Ready flat design.
It's free to use for personal and non-profit projects.
Horwheel is a component to scroll horizontally with mouse wheel. It's cross-browser compatible.