A good idea.
Car horns have not really changed for a hundred years. Other than those novelty horns that play "Bolero" or the like, car horns have always made the same obnoxiously loud noise - whether you are beeping hello to your friends, telling someone to hurry up, or honking simply as retribution.
In addition, there are tons of situations when a honk simply doesn't convey your emotion. How do you honk "I'm sorry" or "Thank you"? It's virtually impossible with the standard hardware. I was discussing this problem with my friend Dan, and his original idea was to have a dedicated "thank you" horn, which could potentially double as an apology horn. From a sound design perspective, this wouldn't be particularly difficult...two short 'beep' or 'boop' sounds, the first at a higher pitch, would probably do the job quite well.
This got us thinking, however, and we tried to figure out how one could convey a whole range of emotions through a car horn. Our solution, as the picture suggests, entails a touch pad with an x and y axis, the extremes of which would correspond to a pure emotion. I labeled these as Anger/Happiness and Grateful/Apologetic, but those could certainly be improved and refined.
The difficult part of this project, of course, would be the sound design, particularly since the sounds should probably be as simple as possible. What does monophonic anger sound like? And is it be possible to make a smoothly variable sound that can shift between anger and happiness, and nail every nuanced emotion in between? More philosophically, if it is possible to find an anger sound, could one find a happiness coefficient?
Another aspect of this, that my designer friends would understand better than I, would be the effect on the user. Would someone be able to eventually become familiar with the interface enough to instantly be able to pick the precise spot that reflects how they are feeling? Righteous indignation, or embarassment, or pride... what would that sound like?
Maybe eventually people could use a device like this to communicate without words. Maybe.
In other words, it's interesting to think about the possibilities of sound design, and its limits.