[bry]

I really enjoyed this book:

"Crypto: How the Code Rebels Beat the Government Saving Privacy in the Digital Age"

http://www.amazon.com/Crypto-Rebels-Government-Privacy-Digit...

Doesn't really teach crypto methods, but it gives a solid (and interesting) lesson about the history and thinking behind cryptology. A good read even if you're not a developer, IMHO

[mattyb]

'Cryptography Engineering' by Ferguson & Schneier is the best.

http://www.amazon.com/gp/aw/d.html?pd=1&a=0470474246

^ I got that link using my BlacbBerry, apologies if it's the mobile version.

[quadhome]

http://en.wikipedia.org/wiki/Books_on_cryptography has an excellent set of recommendations.

[pinksoda]

http://en.wikipedia.org/wiki/Cryptography

Tons of good information on that page. Scroll down to the bottom and check out some of the "See Also" links.