A University of Washington course in Cryptography is available online, including videos of all the lectures (via Bruce Schneier). I've listened to the first lecture and it seems like a great introduction if you're interested in the subject.
Interestingly, he cautions about Schneier's "popular-but-not-good" Applied Cryptography. The course also used Classroom Presenter 2.0, a cool product mentioned by the Tablet PC Education Blog last year.
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