In an attempt to be more diplomatic I’ve decided to change the single digit hand gesture I often display in response to motorist stupidity. So now if you honk at me, try to run me over, spout nonsense like “get off the road!” I will respond with a big thumbs up and a smile.
Just be aware that it probably doesn’t mean what you think it means. It’s just less likely to incite negative emotional responses and possible violence. But it is deeply sarcastic.

Consider the thumb thickness too.