Fresh from the Patent Office to a road near you: Car-to-Car Chit Chat.
"How often have you been driving and wished you could communicate with another driver? Perhaps you'd like to give them advance warning that you intend to slow down, say thanks when they have given way or issue a gentle rebuke for some lapse of road manners on their part.
"Sony is patenting a simple way to make this possible ... "
All together now, everyone who thinks this system would be used to say Thanks, please raise your hands. OK, now let's see hands if you've witnessed a "gentle rebuke" any time within the past decade. Anyone? Anyone at all?
Oh, this is so not a good idea.