1. IT Mill Toolkit
IT Mill Toolkit is an open-source framework, providing widgets and tools for the development of Rich Internet Applications (RIAs). Deliver web applications without worrying about incompatibilities of web browsers, DOM or JavaScript by using standard Java tools.
2. LivePipe UI
LivePipe UI is a suite of high quality widgets and controls for web 2.0 applications built using the Prototype JavaScript Framework. Each control is well tested, highly extensible, fully documented and degrades gracefully for non JavaScript enabled browsers where possible
3. Iwebkit iPhone/iPod touch framework
Iwebkit is the revolutionnairy kit used to create high quality iPhone and iPod touch websites in a few minutes. In the first 4 months of it’s existance the pack has greatly evolved from a basic idea to a project that has reached worldwide fame!
4. Jitsu
Jitsu contains an integrated set of tools to enable developers to build and deploy sophisticated user interfaces for web applications. These include an Xml markup language, page compiler, data binding engine, JavaScript runtime, control library, runtime inspector, animation engine, cross-platform library, Ajax, and back button support.
5. MochaUI
MochaUI is a web applications user interface library built on the Mootools JavaScript framework.Uses: web applications, web desktops, web sites, widgets, standalone windows and modal dialogs.
6. Echo Web Framework
Echo is an open-source framework for developing rich web applications. From the developer’s perspective, Echo behaves as a user interface toolkit–like Swing or Eclipse SWT. AJAX technology is employed to deliver a user experience to web clients that approaches that of desktop-based applications.
7. The Yahoo! User Interface Library (YUI)
The YUI Library is a set of utilities and controls, written in JavaScript, for building richly interactive web applications using techniques such as DOM scripting, DHTML and AJAX. YUI is available under a BSD license and is free for all uses.
8. Sigma Ajax UI builder
Written in javascript and PHP, SigmaVisual is web based visual AJAX UI builder for professional developers. Developers save their time in building up prototype as well as real web applications. TreeBar, TreeGrid, Layout, Menu are supported.
9. WUI Web UI Framework
WUI (Web User Interface) is an MVC framework for writing web UIs in a single language: Java. Write web apps with components, widgets & events, not JSPs. Runs in any servlet 2.3 container. Similar to Model 2 / Struts, only better. Apache-style license.
10. Butterfly Web UI
Butterfly Web UI is a component oriented web framework for Java, like Wicket or Tapestry. The main advantage compared to these frameworks is that Butterfly Web UI integrates naturally with Butterfly DI Container, giving you a state-of-the-art dependency injection container to help you structure and decouple the internal components of your web applications.
11 Yahoo YUI library
The YUI Library is a set of utilities and controls, written with JavaScript and CSS, for building richly interactive web applications using techniques such as DOM scripting, DHTML and AJAX. YUI is available under a BSD license and is free for all uses.