The Rear End

On a day like today, with snow piling fast and tall, with most people staying home (I am guessing to avoid commute as much as to avoid driveway cleaning), with poor visibility and ugly driving conditions, I wonder: why are the means of in-car communication so limited?

It seems that all of those lights and horns were designed with the sole purpose of taking care of "the other guy". E.g. white taillights - I am backing out. Orange blinking light on the left - I am turning. Red taillights - I am stopping. Beware, stay safe!

But why is there no way to communicate that annoying tailgater behind you - to take care of myself?