its sometimes hard to find the horn on some cars, for example on renault peugeot the horn is sometimes on the indicator stork. why?
in situations when you have a split second to react, the horn wants to be as close to where ur hands are - or should be - the steering wheel.
for me, in situations when i were cut up id become moody and follow them...
again with waving, beeping at people on the street is great fun :P
but i don't recommend this or condone it in any way.........
