All these libraries are different, but notable on their own. The true leader of list is Meteor. They received over 6500 stars on GitHub and over $11 Million investment from Andreessen Horowitz. That makes Meteor the promising project in upcoming 2013. Or maybe a most overestimated one? What do you think?
Meteor is an open-source platform for building top-quality web apps in a fraction of the time, whether you're an expert developer or just getting started.
Select2 is a jQuery based replacement for select boxes. It supports searching, remote data sets, and infinite scrolling of results. Look and feel of Select2 is based on the excellent Chosen library.
A small library for manipulating the favicon Tinycon allows the addition of alert bubbles and changing the favicon image. Tinycon gracefully falls back to a number in title approach for browsers that don't support canvas or dynamic favicons. Alerts in the favicon allow users to pin a tab and easily see if their attention is needed.
Yeoman (n) 1. A noble servant, carrying out various duties for the sovereign. Associated with hard toil. 2. Your new favorite web application stack and development tool.
noty is a jQuery plugin that makes it easy to create alert - success - error - warning - information - confirmation messages as an alternative the standard alert dialog. Each notification is added to a queue. (Optional)
Making good-looking graphs shouldn't be hard. Morris.js is a lightweight library that uses jQuery and Raphaël to make drawing simple charts easy.
Metro UI CSS allows to create a Web site in the style of Windows 8 quickly and without distractions on routine tasks.
Gridster is a jQuery plugin that allows building intuitive draggable layouts from elements spanning multiple columns. You can even dynamically add and remove elements from the grid. It is on par with sliced bread, or possibly better. MIT licensed. Suitable for children of all ages.