Edgar Allan Poe
The macabre writer was so into cryptography that the plot of his famous short story, "The Gold Bug," revolved around a secret code. While writing for Alexander's Weekly Messenger, Poe challenged readers to solve two ciphers written by W.B. Tyler. The ciphers remained unbroken for more than 150 years until Louis A. Renza, a Dartmouth professor, speculated that Tyler was actually Poe. The revived interest led to the first cipher being cracked in 1992 and the second in 2000.