A few weeks ago I told my friends 5 year old daughter that I was gonna chain her in the basement and feed her dog food for the rest of her life if she didn't finish her dinner. It was funny until she went home and told her mother what I had said, then it became completely hilarious.
I used to toss my cousion in a sleeping bag upside down and throw him in a closet and lock it.
He's not 17 and listens to a lot of death metal, grind and hardcore, so I made up for my sins.
It was still funny though.