Individual rear turn signals were a hot topic of conversation on CEG around late 2001, with several people IIRC wishing we could have them and possibly trying to figure out a way how.
I saw a flashing third brake light on a modified Honda (Civic? can't remember) in Worcester once last year. It flashed about the same rate as a turn signal would. Initially thought it was the coolest thing in the world, till I followed him for 1/4 mile in city traffic ... very annoying after that!
However, I'm all for fast-flashing lights during emergency stops.
