I am glad to now know about Harold Hering, and I think I'm going to add his story to the reading we're having tonight in NYC.
That said - there are a great many people I admire more than Petrov. Petrov is significant not because he's an amazing person, but because he literally was the person who saved the world, for good or for ill.
It is Petrov Day again, partially thanks to Stanislaw Petrov.
http://lesswrong.com/lw/jq/926_is_petrov_day/