To become better programmers, it's really helpful to have a sense of what's possible at higher levels of skill. I'm curious to hear from HN'ers about master programmers you've personally met/worked with. What impressed you? What were they capable of?
Edit/update: At this point in my learning, people in software I consider $DEMI_DEITY-like (but have not met/worked with) include Peter Norvig (I have PAIP in front of me and think, He wrote this in his mid-thirties? Gah!), Abelson and Sussman (authors of SICP), and some of the people who created the tools I use (Stallman for Emacs, GvR for Python, Hickey for Clojure). As for personally-encountered greatness, there was one fellow at my last firm who later went on to be in the top 5 in the TopCoder competition, whose speed and ability to build the right abstractions were really impressive - that's vague, but at the time, I wasn't good enough to appreciate his skill in-depth either. :)