Sproutcore
JavaScript Application Framework - JS library only
Robotjs
Node.js Desktop Automation.
Wee
Blueprint for modern web development
JayData
JayData is a unified data access library for JavaScript to CRUD data from different sources like WebSQL/SQLite, IndexedDB, MongoDb, ASP.NET WebAPI, OData, HTML5 localStorage, Facebook or YQL. The library can be integrated with KendoUI, Knockout.js, Handlebars.js or Sencha Touch 2 and can be used on Node.js as well.
Conditioner
Frizz Free, Environment-aware, JavaScript Modules
Hinclude
declarative client-side inclusion for the Web
Eve.js
A <3kb JavaScript file providing three simple methods to organize code into CSS namespaces which magically restrict code to the current context, allowing for dramatic reductions to code size and development time.
Abaaso
A modern, lightweight enterprise-class RESTful JavaScript application framework.
Angular Meteor
Combining the simplicity and power of AngularJS and Meteor
Theory
Abstraction layer for cross platform JavaScript.
Loglevel
Minimal lightweight logging for JavaScript, adding reliable log level methods to wrap any available console.log methods
Hasher
Browser history manager for rich media websites
Path.js
Simple, lightweight routing for web browsers
Fluxxor
Flux architecture tools for React
Lodash
An alternative to Underscore.js, delivering consistency, customization, performance, and extra features.
Fetchival
window.fetch wrapper for writing simple and expressive requests
Queue
Yet another asynchronous helper library for JavaScript. 387 bytes minified and gzipped!