Whatever happens, make sure you print out your bingo card before you go, and then throughout the weekend, cross off everything that you see on there. If, by the end of the weekend, you've nabbed five across, you win! And while last year, all you won was the satisfaction of seeing something cool, well heck, let's throw something else into the mix -- if you're the first person to personally show me a completed bingo card by the end of the convention, I'll have a prize waiting for you.
And no cheating! Trust us, there'll be plenty of Paladin complaining at the Q&As -- you won't have to go do it yourself.