TodoMVC : A project which offers the same Todo application implemented using MV concepts in most of the popular JavaScript MV frameworks of today.
rsvp.js : A lightweight library that provides tools for organizing asynchronous code
stream.js : stream.js is a tiny stand-alone Javascript library that unlocks a new data structure for you: streams.
Timeline : Beautifully crafted timelines that are easy, and intuitive to use.
Parsley.js : Javascript forms validation.
Powerful, UX aware & Dead simple.
Rainbow is a code syntax highlighting library written in Javascript.
It was designed to be lightweight (1.4kb), easy to use, and extendable.
It is completely themable via CSS.