What's wrong with a pocket sized notepad and pencil?

Seriously, as someone who used to carry a PDA around all the time (i did my university notes on a newton), I'd have to say that pencil and paper are going to beat the crap out of PDAs. The only thing that could change my mind would be a pda with integrated wireless networking, monster long battery life, and made of something flexible so I don't worry about crushing it all the time.