The Code Book

I read this year a great book on cryptography. Not only is it well written, it offers a glimpse into the world of secret agents. Movies such as Mercury Rising demonstrate the extent to which governments are said to go to prevent a code from being broken.
It all comes down to the value we put on intimacy vs the value the government puts on national security. It is a fascinating account of the push and pull of the flow of information.
I can't find the words to share my enthusiasm of the book. Even excerpts don't do it justice. I think the fun is in looking for a good code and the joy in breaking it. This is renewed many times throughout the book.
I was amazed that I deciphered a sentence published in the local newspaper just by following the rules described in the book. I never managed it before -- I got impatient. This time, I was sure that success would follow if I applied the rules and took my time. It was pure joy.
A link to the book in Amazon follows:
The Code Book : The Evolution Of Secrecy From Mary, To Queen Of Scots To Quantum Crytography (Hardcover)by Simon Singh