i would run over and grab his ass and call the cops.
(well, i say that but when some chick flung the passenger door open and hit my car, a number of years ago, i was so ****ed i walked over and to the driver's door, opened the door and grabbed the guy driving and told him he better straighten his chick out or i was going to put his face through the wind shield and break her teeth on the curb after using her head to try and get the dent out. i say i am going to do things but when it comes to that point in time, it never works out and i embarrass my wife by getting in people's faces and threatening them)