PUBLIC MARKS from parmentierf with tags ide & "open source"

The Open Komodo Project, based on the award-winning Komodo IDE, is a new initiative by ActiveState to create an open source platform for building developer environments. ActiveState has open-sourced elements of Komodo Edit, a free multi-language editor for dynamic languages based on Komodo IDE, to create the Open Komodo code base.

TIBCO General Interface Builder is the award winning AJAX solution for rapidly building and easily deploying Rich Internet Applications (RIA), AJAX components and portlets that look and feel like desktop software.

#develop (short for SharpDevelop) is a free IDE for C#, VB.NET and Boo projects on Microsoft's .NET platform. It is open-source, and you can download both sourcecode and executables from this site.