The final moments of a poker hand are agonizing. The chips are in the pot; your opponent just raised your last bet. Call or fold? What are you going to do? Your opponent, a regular at this Friday night game, looks around the room. He fixes his hair. And then it happens. "So, Johnny, you see the Lakers game last night?" he says. That's all you need: He's bluffing. You know this guy. If he were holding a winning hand, he'd feign nervousness. You bet the bank.