I kept hitting the back of my garage so instead of learning how to drive, I made a gadget.
This senses distance from a vehicle and lights up to show how close. Once you reach the desired distance, it flashes red.
How do you set the distance you ask? There is a handy push-button. Whenever the button is pressed, the device permanently saves the distance.
To power the device, I used the light socket adapter to attach it to my garage door opener. That way, whenever the garage light is on, the sensor is working.
Here's a video of the sensor in action: