I was completely stopped in heavy traffic, and the guy behind me apparently simply wasn't quite paying enough attention to the brake lights and thus didn't quite stop in time. No squealing tires; the first inkling I had that something was going wrong was suddenly getting firmly jostled.
My car is fine (except for a shallow indentation in the bumper that matches a corner and bolt of the guy's front licence plate holder), and I'm fine (except for a vague feeling of achiness in my neck that I assume will be much worse tomorrow); I still have a full range of movement with no pain, no dizziness, nothing otherwise out of the ordinary.
Feudalism: Serf & Turf
(And yes, the first thing I did when I got home was take some ibuprofen.)