Maybe it's someone's birth certificate?

Julian Assange has made a threat. He says he has a secret. If any harm comes to him personally, or if WikiLeaks is somehow wiped off the Web, there will be consequences. "It's locked up so tight that even sophisticated military computers can't crack it open. Assange has said that if he or WikiLeaks croaks, the key gets sent out as well, and the whole world gets to see the great big secret inside. Unless that happens, though, what's in that file is anybody's guess -- and the mystery is what makes it such a powerful life insurance policy." Technology News