I’m obsessive about my windscreen wash in my car. I worry constantly that any second now it is going to run out. I fill it up regularly even when I’ve only used about a teaspoonful.

You can imagine my displeasure, when I was driving down a misty, muddy road and thinking I would have to start using up some of the precious water. Then imagine my pleasure, when the car in front decided to clean its windscreen first, and the water cascaded in a beautiful arc over the top of his car and onto mine as well. Excellent. Clean windows, free water.