In what's almost par for the course for LucasArts adventure games, there's an item (actually two: Bernard's Flux Dynamics textbook and the disappearing ink) that you can use on almost any character and cause a variety of hilarious and unexpected reactions. Among the greatest ones are Oozo the clown (textbook) and the guard tentacle, when Laverne's been let out of jail to go to the bathroom (ink).
Tentacle Guard: Eww! In the grass! Do that in the grass! Lousy humans...
Purple Tentacle: The only three-headed monkey here is in front of us.
Bernard: "Now what am I gonna do?"
Dr. Fred: "I think I made myself perfectly clear. Step One: Find Plans. Step Two: Save World. Step Three: Get Out Of My House! Now let's get cracking!"
Bernard puts a hamster in the deep freeze for Laverne to recover in the future. She revives the hamster in a microwave oven, while Breaking the Fourth Wall to tell us that kids who try this in real life are taken away.
When Hoagie has to push the kite, simply ignore Benjamin Franklin's signal and do nothing: