The Zodiac Killer, who murdered at least five people in 1968 and 1969 and claims to have killed many more, sent taunting letters to California newspapers. One of the message consisted of a series of letters and symbols in a code that no one could decipher. Now a team of codebreakers operating in three different countries say they have finally deciphered the letter known as cipher Z340.
I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME
THAT WASNT ME ON THE TV SHOW
WHICH BRINGS UP A POINT ABOUT ME
I AM NOT AFRAID OF THE GAS CHAMBER
BECAUSE IT WILL SEND ME TO PARADICE ALL THE SOONER
BECAUSE I NOW HAVE ENOUGH SLAVES TO WORK FOR ME
WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE
SO THEY ARE AFRAID OF DEATH
I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW LIFE IS
LIFE WILL BE AN EASY ONE IN PARADICE DEATH
The FBI has accepted their decryption. The video above explains how they did it. You can read more at the San Francisco Chronicle, or if that's blocked by a paywall, at Zodiac Killer Facts.