FlexSlider is a free responsive jQuery slider toolkit. Supported in all major browsers with custom navigation options and touch swipe support.   FlexSlider - Features: An awesome, fully responsive jQuery slider toolkit. Simple, semantic markup Supported in all major browsers Horizontal/vertical slide and fade animations Multiple slider support, Callback API, and more Hardware accelerated touch swipe support Custom navigation options Compatible with the latest version of jQuery  

PhoneGap is an open source solution for building cross-platform mobile apps with standards-based Web technologies like HTML, JavaScript, and CSS. It allows you to write an app once with HTML, CSS and JavaScript, and then deploy it to a wide range of mobile devices without losing the features of a native app.  

Quicksand is a jQuery plugin for reordering and filtering items with a nice shuffling animation.   At the very basic level, Quicksand replaces one collection of items with another. All you need to do is provide those sets of items. You can do it in a couple of ways: Use plain HTML, like an unordered list. Download data by an Ajax call Transform HTML items by JavaScript (for example, sort them differently)  

Mosaic Flow is a Pinterest like responsive image or HTML grid plugin for jQuery.    Mosaic Flow - Features: Simple and easy to install. Responsive (shows as many columns as needed). Very fast. Only 1.5 KB (minified gzipped). You can use bare <img> tags or arbitrary HTML.   

jQuery Grid 'Em is a simple jQuery plugin that allows you to evenly apply horizontal spacing on a list of items across multiple rows on a page.   

jQuery contextMenu was designed for web applications in need of menus on a possibly large amount of objects. This contextMenu treats the menu as the primary object. That means, that a single menu is defined that can be used by multiple objects. This context menu plugin doesn't need to bind itself to triggering objects. This allows injecting and removing triggers without having to re-initialize or update contextMenu.   This plugin can provide a simple list of clickable commands, or offer an in-

WordCount.js is a client-side JS and Node.js library that counts bytes, words, lines, chars, and calculates the longest line of a file using the HTML5 File API.  When a file is uploaded using the file input element with the given input selector then the number of bytes, words, lines, chars, and the longest line in the uploaded file are calculated and then callback is called.  

Colorbox is a lightweight customizable lightbox plugin for jQuery. It accepts settings from an object of key/value pairs, and can be assigned to any HTML element. Colorbox - Features: Supports photos, grouping, slideshow, ajax, inline, and iframed content. Lightweight: 10KB of JavaScript (less than 5KBs gzipped). Appearance is controlled through CSS so it can be restyled. Can be extended with callbacks & event-hooks without altering the source files. Completely unobtrusive, options are

Font Sizer is a highly configurable, unobtrusive jQuery plugin that allows users to adjust the font size of specific area(s) of text on your website. It's lightweight, easy to configure and adds a nice bit of functionality to your blog, forum or news site.  

SlickQuiz is a jQuery plugin for creating pretty, dynamic quizzes. There are many options available. You can chnage the number of questions to load from the question set in the JSON object, sort questions and answers randomly, prevent submitting a question with no answers and so on.