Rupa-vilasa: Prabhupada was in his room in Vrindavan discussing various preaching plans with Akshayananda maharaja when Prabhupada said, "So, what should we do?" Akshayananda maharaja replied, "Prabhupada, we will just have to become Krishna conscious." Prabhupada said, "Another impractical solution." That was one of the most hilarious exchanges I heard.
Another story is when a devotee said, "I am the most fallen, Prabhupada" and Prabhupada said, "You are not the most anything." This devote was trying to show how humble he was. He wanted credit for being the most something, and Prabhupada said, "You are not the most anything." Prabhupada was so quick and so funny, so sharp and so sarcastic, but you never felt offended by him. Even if the joke was at your expense, you had to admit it was really funny, and it always had an instructive edge to it and it was merciful because he was trying to help you. Prabhupada was cutting through that to put us more in touch with reality.