The idea of having a message board on the rear of your car is pretty cool. A buddy of mine got tired of idiots riding his ass or following behind him with those superbright blue hgihbeams. His solution was to buy some big spotlights that you see on jeeps and things for trail riding. WELL he mounted them facing backwards on his truck wired to a simple switch in his cab. When someone wont turn off their hgihbeams or wont get off his ass he simply turns the lights on for a second and they back off right away. He never leaves them on because they could get blinded and crash but once they get a lil taste of their own medecine they back off. Illegal? i dont know. Effective. VERY