I'm surprised that this hasn't been posted yet.
Robert Hanssen, infamous FBI traitor and spy for the Soviets, was found dead in his cell in the Supermax prison in Florence, CO on 5 June. (Actually, he wasn't found "dead" - he was found "unresponsive" which is the same thing. Why do these morons do that? But I digress.)
The secrets that Hanssen sold to the Soviets paint him as one of, if not THE worst, spies in American history.
He was sentenced to 15 life terms without the possibility of parole in 2002.
His Wiki article says he was 79 and that his death is believed to be from natural causes.