Henry Grabar is a staff writer for Slate’s Moneybox and a former fellow at CityLab. He lives in New York.
Pretend there's a huge rock in their path, obviously.
A good prank strikes a favorable balance between effort and result.
The "invisible object" prank give so much bang for your buck, we're shocked we haven't seen it before. In this video from Whale Studios, drivers in Amsterdam are duped into thinking they are about to smash into a rock, or something.