This is for computer people only: Ever heard of the Eiffel programming language?
It's supposed to be an super-duper-ultra-elegant object-oriented development platform, and its proponents think that it is superior to Java and C++. But i haven't heard of anyone actually using it.
Apparently the canonical implementation of Eiffel, EiffelStudio is moving towards becoming fully Free Software. The IDE is released under a modified GPL, much like Qt. It runs on Windows, and is supposed to work on Linux, FreeBSD, MacOS, some other Unices and even VMS.
The IDE is very impressive in the sense that it has a lot of toolbars with colorful buttons. The terminology, however, is quite different from what you may be used to in NetBeans, MS Visual Studio or KDevelop. The words "retargeting", "pull up", "feature", "cluster", "contract" and even "text" don't mean what you think they mean, but once you do the guided tour in the Help system it becomes clearer. There are also very impressive Eiffel training presentations.
I have no idea what is it good for, but every day i dedicate a few minutes for studying this thing. Did i mention the colorful toolbar buttons already?
(Tip, if you are trying this: The guided tour mentions ACE files. Actually these are ECF files. The documentation wasn't completely updated for version 5.7.)