This is a nifty idea. Fun with crypto for small message spaces like Twitter.
Here is a nice walk-through on completing a cryptography challenge.
Wikibooks in putting together a book on cryptography. Go check it out and contribute if you can.
Here is a google talk from Nate Lawson on common cryptology flaws.
Stop what you are doing and go read this. Yes all of it. Then send it to your programmers.
The annual FBI cryptography challenge is up. Go get em'.
The Princess of Antiquity is back and picking up her Non-technical series on Cryptography. I have pointed to previous posts before. Good stuff.
I've use BeCrypt products for quite some time and have found them to be excellent. They now have a library that is FIPS 140-2 certified.
Ed Skoudis has another hacker challenge up.
If you use password protected Outlook PST files, you might want to go take a look at this video. Actually, you should go take a look regardless.
Didier has part 1 up to the Authenticode challenge he posted. Very interesting stuff.
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