Mithril.js
A Javascript Framework for Building Brilliant Applications
Keymaster
A simple micro-library for defining and dispatching keyboard shortcuts. It has no dependencies.
Ect
Fastest JavaScript template engine with embedded CoffeeScript syntax
Layzr.js
A small, fast, modern, and dependency-free library for lazy loading.
jsMessage
Custom messages, alerts, confirmations
Crypto Js
JavaScript library of crypto standards.
LABjs
Loading And Blocking JavaScript: On-demand parallel loader for JavaScript with execution order dependencies
Jwerty
Awesome handling of keyboard events
ICanHaz.js
A clean solution for templating with Mustache.js and jQuery or Zepto
Venus.js
where bugs go to die
React Templates
Light weight templates for react
Jsblocks
Better MV-ish Framework
Lazy.js
Like underscore.js, but lazier
Highland
High-level streams library for Node.js and the browser
Stimulus
A modest JavaScript framework for the HTML you already have
Spine
Lightweight MVC library for building JavaScript applications
Fast.js
Faster user-land reimplementations for several common builtin native JavaScript functions.