Human communication is a sophisticated and sublime thing. The other day I was driving and a motorcyclist with a toot of his horn, a point to his turn signal and a rude gesture communicated his displeasure at my lane changing technique.
horn toot + point point + rude gesture = "Excuse me, may I have your attention, I feel that you did not sufficiently use your turn signal, you wanker."
Incredible, no? And with a gentle tap of my bumper to his back tire I made my rebuttal that we both tacitly agreed ended the discussion.