I'm not sure how this started, but now whenever I have my two grandsons ( 2 and 3 yrs old) in the back seat of my car, going to pick up their Mommy at work, I sing 'Trick or treat, smell my feet, give me something good to eat". The 3 year old will say 'faster!' and I keep singing it faster and faster. Eventually, when I can't sing any faster, he'll say "Grandma, you funny!". No other song gets this reaction.