A somewhat astonishingly good explanation of AES via stick figures (yep, stick figures):
Very funny, and surprisingly good pedagogy. I'm pretty much a math obsessive, and I now feel like I understand the 'byte xors == polynomial field arithmetic' better than I ever have before.
(the release form in the middle is maybe the best thing ever -- it's rare to see a good math joke, and I can't tell you the last time I saw a good math/interpretive dance joke. And thus, I celebrate it).