Kendo UI Core
A modern dialog library which is highly configurable and easy to style. #hubspot-open-source
CSS3 Animations with special effects
:dango: An interactive and responsive charting library
Modern Prototyping Tool
A library optimized for concise, principled data graphics and layouts.
Timeago is a jQuery plugin that makes it easy to support automatically updating fuzzy timestamps (e.g. "4 minutes ago").
Markdown parser, done right. Commonmark support, extensions, syntax plugins, high speed - all in one.
Super-smooth CSS3 transformations and transitions for jQuery
An awesome, fully responsive jQuery slider plugin
Simple tooltips made of pure CSS