Snowden's Dead Man's Switch
Edward Snowden has set up a dead man's switch. He's distributed encrypted copies of his document trove to various people, and has set up some sort of automatic system to distribute the key, should something happen to him.
Dead man's switches have a long history, both for safety (the machinery automatically stops if the operator's hand goes slack) and security reasons. WikiLeaks did the same thing with the State Department cables.
"It's not just a matter of, if he dies, things get released, it's more nuanced than that," he said. "It's really just a way to protect himself against extremely rogue behavior on the part of the United States, by which I mean violent actions toward him, designed to end his life, and it's just a way to ensure that nobody feels incentivized to do that."
I'm not sure he's thought this through, though. I would be more worried that someone would kill me in order to get the documents released than I would be that someone would kill me to prevent the documents from being released. Any real-world situation involves multiple adversaries, and it's important to keep all of them in mind when designing a security system.