I let my players do a Knowledge Religion check to figure out the weaknesses of the end boss of the Tomb of Horrors. They succeeded, and I suggested that a "Word of Power" (Any Powerword) or a "Biting of its eye" (Eyebite) would be the most effective. Now, they had been 2-3 rounds in of combat at this time, and they had all just barely avoided the boss's instant death attack. When it comes to my friend's turn, he bursts out laughing and declares: "I bite its eye!" This is followed by some laughter, and I declare that the boss should make a reflex save to avoid it. Soon, everyone is either casting support or Biting the thing's eye. Eventually, they kill it though some vicious Biting of the Eyes, and beat the Tomb of Horrors.