This old-school prank has been driving people nuts for generations… and it still hits like a symphony of confusion. 
 
Just slip this tiny metal tip onto the end of a car’s exhaust pipe and step back. As soon as they hit the gas, their ride transforms into a rolling tea kettle, letting out a high-pitched whistle that follows them down the road.
 
The best part? It builds… and builds… until they’re convinced their car is either haunted or auditioning for a cartoon. Meanwhile, they’ve got no clue where the noise is coming from.