>When you're doing crypto, don't try to get clever.

You know, this was a little hard to swallow, because I consider myself to be such a clever fellow.

I didn't mean to be such a downer. If you're interested in crypto, don't give up. Just use your hubris somewhere it will be productive. Instead of saying to yourself "I can design my own cipher," start with "I can figure out why these other ciphers are designed the way they are." That means both understanding how encryption algorithms work, and what attacks are possible against them. A lot of amazingly smart people have thought about that, and you can learn a lot from their work. So find yourself a good book and dig in - that's what I've been doing.