I'm currently writing real-time music entertainment software at Harmonix Music Systems (http://www.harmonixmusic.com) in Cambridge MA, concentrating specifically on automated composition. My background before that was writing 3D computer games.
I'm still searching for the Holy Grail of programming. Some things that I have decided are the Right Thing: Emacs (EmacsRules!), PythonLanguage, RubyLanguage, ProgrammersNotebook. LiterateProgramming feels right in many ways (and I have written a few tools for it), but the practice doesn't live up to the theory. I'm excited about a lot of ExtremeProgramming ideas, which I have just encountered here.
SmalltalkLanguage is pretty neat, but it seems so wedded to its environment that it's difficult to use it for a new project. Many of the things I like about it are present in RubyLanguage.
At Harmonix we have been dipping our toes into some XP, mostly through regular PairProgramming, which I like very much.