What is the most annoying gift you have given to a family member for "revenge?"
When my nephew was 3 years old, I gave him 3 old school style bicycle horns (you know with the black bulbs). I told him that they were great alarm clocks for his mommy and daddy to wake up with on the weekends. I said he should hide them in case his daddy tried to keep it for himself. My brother and his wife are still searching for the ultimate payback after 25 years.