The Code Book
by Simon Singh [652.8 Sin]

Battle of Wits: The Complete Story of Codebreaking in World War II
by Stephen Budiansky [940.548 Bud]

Enigma
by Robert Harris

Between Silk and Cyanide: A Code-maker's War - 1939-1945
by Leo Marks [940.548 Mar]

The Secret Speech
by Tom Rob Smith

The Lost Symbol
by Dan Brown

The Lives of Others
[DVD Lives]