Stimulus
A modest JavaScript framework for the HTML you already have
Sherlock
Natural-language event parser for Javascript
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
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.
Wee
Blueprint for modern web development
Angular Meteor
Combining the simplicity and power of AngularJS and Meteor
Theory
Abstraction layer for cross platform JavaScript.
Hasher
Browser history manager for rich media websites
Canjs
Can do JS, better, faster, easier.
Path.js
Simple, lightweight routing for web browsers
Lodash
An alternative to Underscore.js, delivering consistency, customization, performance, and extra features.
Queue
Yet another asynchronous helper library for JavaScript. 387 bytes minified and gzipped!
Kefir
A Reactive Programming library for JavaScript
Weld
Template antimatter for Node.js (Browsers too!)
Simplate
A simple, but powerful, templating engine for JavaScript.