From the Lost Files of Clever Conversations . . .

While Gregg and Cosette were driving one day, Cosette started commenting on the lights and controls inside the ceiling of the Suburban, saying they looked like a robot. The conversation then continued something like this:
C: "Speaking of which, why do cars have wheels?"
G: "What would they have if they didn't have wheels?"
C: "Slides"
G: "Wheels probably go faster."
C: "Oh . . . speaking of another which, why don't snakes have arms or legs?"