Yeah, that part with the old man and the flashing screen was pretty funny. Another good one is when Luffy smacks smoker in the back when he was talking to ace in the restaurant in Alabasta. The face ace & Smoker made was hilarious.
Finally when Luffy and his crew just set sail again from Alabasta in the manga chapter 217-16 and everyone is insulting Zoro and Luffy calls him "Three Swords" then Sanji Says: Thats not an insult. Then Luffy calls him "Four Swords" That Was Hilarious!