Eclipse is the premier example of what a large company can achieve though open source. Originally developed and still backed by IBM, Eclipse is a robust, stable integrated software development environment with widespread support for a large number of languages, features, source code control systems, and so on. Eclipse is by far the best development environment we've seen. The Eclipse community is dynamic and vibrant, with a large number of supporters that range from large corporations to individual developers.
It's very good and it just keeps on getting better with each new release.
Eclipse is also an application development framework (the software development environment is simply the best example of an Eclipse application). Application developers can use Eclipse to get a massive head start on building first class applications that run on multiple platforms.
