The AutoPark 2000. Tell you what, there seem to be an awful lot of bad parkers in this world. Still, better than nosy parkers, eh? $29.99.
The Auto Park 2000 from American Technologies Network provides parking and backing-up safety for your vehicle with powerful sensors, a microcomputer and a speaker that emits warning beeps as you approach objects in reverse. It offers 3 different zones that are customizable so you can set the distance to your comfort level. The system is designed to easily install on a standard license plate and includes all the parts needed.