Parsley.js
Validate your forms, frontend, without writting a single line of javascript!
Sisyphus
Gmail-like client-side drafts and bit more. Plugin developed to save html forms data to LocalStorage to restore them after browser crashes, tabs closings and other disasters.
Validatr
Cross Browser HTML5 Form Validation.
Colorpicker
jQuery UI widget for color picking (similar to the one in Microsoft Office 2010).
Formvalidation
The best @jquery plugin to validate form fields. Designed to use with Bootstrap + Zurb Foundation + Pure + Semantic UI + UIKit + Your own frameworks. Star it. Try it. Buy it :)
J Query Mask Plugin
A jQuery Plugin to make masks on form fields and HTML elements.
Tus Jquery Client
A jquery plugin implementing the tus resumable upload protocol.
Flexi Color Picker
A pure JavaScript color picker - no images, external libraries, CSS or 1px divs.
jQuery Steps
A powerful jQuery wizard plugin that supports accessibility and HTML5.
Zxcvbn
zxcvbn, named after a crappy password, is a JavaScript password strength estimation library. Use it to implement a custom strength bar on a signup form near you!
Completely
A fresh take on autocompletion for a wonderful user experience
H5F
A JavaScript library that allows you to use the HTML5 Forms chapters new field input types, attributes and constraint validation API in non-supporting browsers.
jQuery Timepicker
Adds a timepicker to jQueryUI Datepicker
Autosize
jQuery plugin for dynamic textarea sizing
jQuery.maskedinput
jQuery Masked Input Plugin
At.js
Add Github like mentions autocomplete to your application.
Validetta
A tiny jquery plugin for validate your forms