Keeping Tailgaters Away
There’s a universal unwritten rule that tailgaters are the worst people in the world. Why is it other motorists’ fault that you, Mr. or Ms. Tailgater, left late for your appointment? Not only are you putting your life at risk, but you’re also testing the patience of normally kindhearted folks and forcing them to brake-check you, which then becomes an entirely different problem.
But this vehicle owner’s passive-aggressive way of dealing with tailgaters is what true engineering is all about. They welded a pipe wrench onto the back bumper of their truck to warn tailgaters that if they get too close, this wrench will fly off and break your windshield. Of course, because it’s welded on, it won’t happen, but the threat is still there.