Gorm (Graphic Object Relationship Modeller) is a GNUstep application for building user interfaces and application objects relationships. Its major features include drag-and-drop creation of GUI elements from palettes, run-time loading of additional palettes, direct on-screen manipulation of GUI elements, manipulation and examination of objects via inspectors, and creation of connections between objects using mouse. It is a clone of the former NeXTstep (currently OS X) "Interface Builder" application.
Webwidgets is a framework for writing Web applications as if they were desktop applications. It employs the same programming paradigm as GTK, Qt, etc. with a tree of widgets with callbacks for events such as a button press. It encapsulates page loads, session data, form handling, etc. into widgets with their own state. Webwidgets is focused on code reuse, rapid prototyping, and separation between graphic design, interaction design, and application logic. It is implemented in Python and uses the Webware application server framework.
JGraphpad Pro is a complete application framework for rapid development of JGraph tools. It is meant for developers who wish to provide a stand-alone, rich-client graph application. The user interface is configurable with XML, and it uses a plugin architecture for extra functionality. It features a wide range of application components like palette, overview, the ability to export to many image and XML formats, copy and paste, drag and drop, rich text labels, database or backend connectivity, and visual complexity management. You can use it to create workflow editors, call graphs, CAD tools, network diagrams, database visualization tools, and more.
XUIML for Adobe Flex is a framework and markup language to create Adobe Flex user interfaces quickly and without coding a single line of ActionScript. The XUIML terminal connects to any SOAP or RESTful Web service and expects simple UI instructions such as "open window", "add tab panel", or "draw textbox", which are then rendered as Adobe Flex widgets.