Osama

After numerous rounds of "We don't know if Osama Bin Laden is still alive,"
Osama himself decided to send George Bush a letter in his own handwriting to let him know he was still in the game.

Bush opened the letter and it appeared to contain a single line of a coded message:
370HSSV-0773H

Bush was baffled, so he e-mailed it to Condi Rice. Condi and her aides had no clue either, so they sent it to the FBI.

No one could solve it at the FBI so it went to the CIA, then to the NSA. All to no avail.

With no clue as to its meaning, they eventually asked Britain's MI6 for help.

Within minutes, MI6 cabled the White House Chief of Staff with this reply:
"Tell your President he's holding the message upside down."