James Randerson we asked who were your top 5 fave scientists (well, four because I threatened to duff up anyone who didn't include Charles Darwin. Possibly a little illiberal.) John Hawks posts his 4 here and includes Leo Szilard. Thousands of people every day walk heedless across the junction in London where he had the eureka moment which many years later led to the first nuclear fission reaction and the atom bomb. I'll walk across it myself tomorrow en route to seeing Darwin's fossil megatherium.
Oh, and doing some Beagle Project meeting stuff, too.