I work for a small technical consultancy in the banking industry, based in NZ. My education was at the theoretical end of computer science (and even logic) but I'm a generalist and like to work on things that are practical or at least yield visible results sooner rather than later.
Currently/recently working on:
- a compiler, just for the fun of it. Input language has C-like syntax but a few higher-level features like tuples and first class functions (including closures). Target language is i386 machine code, linkable with C in Cygwin and Linux. Implementation language is... C (for added fun!).
- a user-mode filesystem, in Windows and Linux. It doesn't have any special features, it's just a chance to play around with B-trees, etc.
- a multithreaded Barnes-Hut galaxy simulator.
- a sequel mod of Star Control 2: The Ur-Quan Masters.
- a lot of work stuff, that you really don't want to hear about. ;-)
The sequel mod, Project 6014 (working title), had a release on 30 September 2010.