I've been waiting for a long time for an item like this...

It's a circular LED display you prop up in your car window with 5 different messages you can remotely put up there to "talk" to other drivers around you.
When you're driving your car there are times when a single finger gesture can perfectly express your sentiments to a fellow vehicle operator. Although this is a relatively efficient form of non-verbal communication, we would like to present a device that brings some technology to the table.
The Driving LED Emoticon is a battery powered, wirelessly controlled message sign that can be attached to the rear window of your car via the included suction cup. A remote control unit is kept in the front of the car (fixed to front window, dash, or laid in a storage compartment) to activate the messages by pressing one of its buttons.
It can display any one of five different messages - smiling face, frowning face, "Thanks", "Back Off" and "Idiot". We will, of course, leave it up to you to decide which of these messages suits your particular situation - but we do think it's nice to have a device that allows you to more clearly express yourself to other drivers.
While the choices are pretty limited but hopefully, this is just the beginning...
I want an LED that not only says "Back Off" and "Idiot"... but also says "What the F*CK are you doing??" and "Use your turn signal!!" and "AZZHOLE!"
Of course I could also use one that could say "Yikes! Sorry!" and "My bad.."