What ever happened to the ladder?
Anyway, how about a prank that backfired? My friend and I thought it would be funny to throw a 5 gallon bucket full of our most recent dumps/piss onto the front door of the neighborhood dick wad. After we both deposited our treasure in the bucket, I walked up to the door and prepared to launch. I was laughing so hard at the thought of doing it, that I wasn't thinking straight when I grabbed the wire handle with one hand and the bottom of the bucket with the other hand and proceeded to send the gift basket toward the door... well, the hand holding the bottom of the bucket slipped off and the momentum sent it flying forward, but my other hand was still holding the wire handle. If you can picture the physics, you'll see the humor. As it swung around, I was instantly covered in mine and my best friends turd-soup. Not a drop got on the door, but all of it ended up on my face, in my hair, and all down the front of me.
I think I was like 29 when this happened.