I've often wondered if his sense of purpose, and ability to continue working are what have contributed to his longevity. Certainly inspiring to see what he has accomplished in his lifetime so far.
Incidentally, he did try to carry on coding using Dragon Dictate, but it was painful to watch. I wonder if speech recognition has come on any since then? Apple’s Siri seems fairly remarkable although I haven’t had a chance to use it yet. Is anyone on HN coding by speech?