Hinclude
declarative client-side inclusion for the Web
Imagesloaded
JavaScript is all like "You images done yet or what?"
Use.js
An AMD/RequireJS plugin for consuming incompatible JavaScript files.
Jsviews
Interactive data-driven views, built on top of JsRender templates
Fishbone.js
A super lightweight (½kb) JavaScript library with automatic method chaining, automatic context binding, event support and simple inheritance. c-{{{-<
Bootstrap Ajax
A library for adding declarative ajax functionality to your website
Sticky Kit
A jQuery plugin for creating smart sticky elements
jTypes
jTypes is the most comprehensive and robust JavaScript library for overcoming differential inheritance with prototype-based objects. Its lightweight yet powerful design provides web programmers on any platform or browser the ability to emulate classical inheritance where objects are defined by classes.
Tempo
Tempo is an easy, intuitive JavaScript rendering engine that enables you to craft data templates in pure HTML.
Px Loader
PxLoader is a simple JavasScript library for creating preloaders and resource downloaders for HTML5 apps.
Mjml
MJML: the only framework that makes responsive-email easy
Min Pub Sub
198 byte publish/subscribe messaging micro-framework
Winjs
WinJS project by Microsoft Open Technologies
Weld
Template antimatter for Node.js (Browsers too!)
Pencilblue
Full stack online publishing and CMS for Node.js
Simulacra
One-way data binding for web applications.
Webpack
Packs CommonJs/AMD modules for the browser. Allows to split your codebase into multiple bundles, which can be loaded on demand. Support loaders to preprocess files, i.e. json, jade, coffee, css, less, ... and your custom stuff.