I develop mainly on Linux, but in a cross-platform way. My weapons include (in rough descending order of preference) C++, HTML5/CSS3/JS/WebGL, Bash, FreeBASIC, Python, C, PHP.
I have not created these projects, but contributed quite much code to them.
Smaller scale contributions.
Small but complete games of the roguelike genre.
Also related:
Interesting games that have not seen updates for some time, but I hope to pick up again in the future.
These were done years ago and won't be developed further.