Most of the newest cars have a “Back-Up Sensor” that warns the driver before the rear bumper actually comes in contact with something.
Most people probably think that this valuable feature came out of the minds of engineers, but it was recently disclosed that the concept was first developed by a Chinese farmer.
His invention was simple and effective. Scroll down to see a photo of his Back-Up Sensor. It emits a high-pitched squeal when the vehicle backs into something.