I've had two "love taps" from behind, one by a tailgater in dense traffic, one by a lady putting on makeup while driving.
Then I got rear-ended by some punk teen in his hopped-up Tacoma with a big tacky add-on tach, gauges on the a-pillar, etc. That impact lifted the rear of my Miata and twisted her lengthwise. Instant kill. I was ok, the car died protecting me. It was a fun 10 years that I had that car, and I still miss her.
So now, whenever I stop at a light or stopsign, or when in traffic which is slowing down, I keep an eye on the rear view mirror. If I see an approaching car and I think they're not stopping -- or if I actually *see* them working the phone, I flash my brakelights and honk the horn lots. Saved me already once, for-sure. Guy looks up and the nose went down, he was hard on the brakes. Then he looks up, as if saying "What?!"