The very cool thing about Eclipse and I think often under stated is that Eclipse has enabled an entire industry of domain specific IDE’s. Besides support for basically any language you can think of, there are also IDEs for specific technologies.
Some recent examples that have come to my attention. 1) You want an IDE for Event Stream Processing, StreamBase just announced one, 2) What about an IDE for doing development for MIPS or NIOS embedded processors, 3) IVR applications, 5) or how an IDE for Second Life? Now that sounds cool.
Yes, Eclipse has become the dominant Java IDE but in many ways I think a greater achivement is that it has truly become the universal IDE platform.
btw, I am always interested in hearing about different Eclipse based IDEs. Feel free to add a reference as a comment or better yet list your solution on EPIC.