Audiovox Universal reverse parking sensor
 

I came across this item at the Crutchfield and Amazon websites and it seemed like the answer to my prayers. It's a bar that attaches to your license plate and has three proximity sensors plus a beeper that signals how close you are to objects behind you. Sounds great :) Works not so great :(

CAREFULLY following the instructions after removing the trunk liner (see my 'Save Them Clips' thread) the unit installed beautifully,and looked great on the car; but when it came to working, the unit measured every object as though it was three inches away. I followed all troubleshooting instructions to no avail. So back in the box and back to Amazon it went. Then I had to pay $30 to replace the clips for the trunk liner.

If anyone else wants to try this item, I'll be interested to see a post on your results.