I have been thinking about getting something like this.
Amazon.com: New Wireless Helmet Brake Light 18 LEDs for Motorycles: Everything Else

 

Interesting. Not a bad idea having a light high up like the 3rd light on cars. It may help a car not directly behind you see that you are stopping.

I am going to get the tail light modulator with the front, it blinks several times then steady, but that won't help the the second car back.

I am more worried about the side and front collisions as they are what happen most. Someone pulling out at an intersection or from the side of the road (from another street or where ever).

I cover the brake at all times when there is a car that has the potential to pull in front of me. I pretend that every car is out to get me. Kind of like a game.

 

Hate to break it to you... it's not a game... they ***ARE*** out to kill you! No doubt in my mind...