It has only recently been announced that Stanislav Petrov, a Soviet Lieutenant Colonel, died back in May of this year. He was profiled by the BBC, and we all have him to thank as when the Soviet radar showed that the USA had launched a nuclear attack in 1983, he judged the reports to be false and the technology faulty - a decision which is said to have prevented an erroneous retaliation by the Soviet Union.
Edit: The Independent, Daily Mail, Daily Mirror, The Sun, Daily Telegraph, The Times, Guardian, BBC obituaries.