After numerous rounds of: "We don't even know if Osama Bin Laden is still alive", Osama himself decided to send George W.Bush a letter in his own handwriting to let him know that he was still in the game.
Bush opened the letter and it appeared to contain a coded message:
Bush was baffled, so he E-Mailed it to Colin Powell. Colin and his aides had no clue either, so they sent it to the FBI. No one could solve it there, so it was sent to CIA, and then to NASA, then to the Secret Service. With no clue to its meaning, they eventually asked Britain's MI-6 for help. MI-6 cabled the White House;
"Tell the President he's holding the letter upside down!"