I program.
Some of my spare time is occupied by a few programming hobby-projects, including a game engine. They are written in the C programming language (the 1999 standard). When the time is right I will release the source code for anyone curious, but it is not public at this time.
The programming language I am most comfortable with is C. I have also worked in Java, Python, R, Emacs Lisp, C++, assembly for x86_64 CPU architecture, and Minecraft redstone.
I do almost all my computer work in GNU Emacs. This includes programming, but also typing up math in LaTeX.
~Alex Stephens