A rare and fully-functional German Naval four-rotor Enigma enciphering machine (M4), is viewed at Bonhams New York on October 22, 2015.  The machine that headlined the auction "Conflicts of the 20th Century" at Bonhams New York on October 21, sold for for $365,000 USD including premium which set a world-record.  Representing the scarcest of the German enigma machines, the M4 was built in 1943-45and up to 150 machines survived from the approximately 1,500 built.   AFP PHOTO / TIMOTHY A. CLARYTIMOTHY A. CLARY/AFP/Getty Images