Eclipse Project: A project aiming to provide a universal toolset for development. Open Source IDE, mostly provided in Java, but the development language is independent and can be extended by plugins

NetBeans: Fully-featured Java IDE written completely in Java, with many modules available, such as: debugger, form editor, object browser, CVS, emacs integration, scripting support, make, Ant, and unit testing. [Open Source, MPL-like

Professional Uniface Users Univers: Independent, unofficial site for uniface developers. Downloads, hints and tips