Another cool program that I use in my job is codeblocks
“Code::Blocks is a free C++ IDE built to meet the most demanding needs of its users. It is designed to be very extensible and fully configurable…”
…ok, ok. Until here nothing awesome… but… the power of this IDE is the multiplatform concept. Like java says: “program once, runs everywhere”. With only one project file, you can compile and run your application in Windows, Linux and MacOSX.
This is my little contribution to open-source cause: