Hi Neal,
I have this problem all too often. I flash tail light (never works), then I turn around and look at them, holding up my left hand as to say "what are you doing?" Flash tail light again, then usually pull over and let them pass. As I watch them go by, I note that they almost always have a cell phone glued to their ear, 6 out of 10 are teenage girls. The other 4 are 3 soccermoms and 1 man in a suit.
People don't think about it, but if you rearend a car, you damage vehicles and maybe hurt someone. You rearend a motorcycle - SOMEBODY DIES!
Cell Phones, should be outlawed nationally while in motion.
I was at a shopping center yesterday and once again saw someone get in their car, start it and got the cell phone out to call someone before they put their seat belt on. For GOD's sake - That's An Addiction.
Possible solution to tailgaiting:
1. Carry some glass marbles in a handlebar pouch, and flip one over your shoulder onto the windshield (windscreen) of the offending vehicle. Marble should shatter as it bounces off and may damage windshield of said vehicle. It will also create a noise that gets drivers attention.
2. Paint Balls! I know they are too tough to break with the minimal impact created by the marble flip. If the paintball could be made weaker (warming or slightly cutting the surface) it might splatter, forcing THEM to pull over and allowing me to continue my journey.

AnyWay, I guess you can tell, I'm gonna get my butt whipped one day following a road rage incident. Maybe I could throw my cell phone at them.

Ride Safe, Stay Invisible (they can't see you anyway), And Stay Outta Their Way,
Dennis


Ride Safe, Dennis Triumph, it's how I live and what I ride.