There’s a fairly limited number of ways for you to communicate a message to someone else on the road, and the most popular one unfortunately involves a finger that should in most cases remain unflipped. That doesn’t mean you always want to convey a message of aggression; maybe you want to thank someone for letting you merge, or you just want the world to know you’re in a happy mood. The Drivemotion LED Car Sign allows you to quickly access 16 different preset messages or faces with the touch of a couple of buttons, ranging the gamut from “Sorry” to “back off”. They’re all displayed through LEDs on a 6-inch wide board that you affix to your rear window with a suction cup.
Now, be aware that this may not be legal in your state or jurisdiction, so it’s up to you to check on that. But if you’re in the clear and the idea fancies you, it’ll cost you $40.