A friend of mine (Jon) works as a Highway officer and because of this he spends a lot of time driving up and down motorways with not much to do but think.
As some point in his boredom induced thinking he noticed that many cows in the fields were quite dirty and started to ponder the economics of a mobile cow wash that he could drive up and offer to farmers as a service. I have no doubt that the idea was just a whimsy to pass the time in the car and to entertain people with as a stupid idea.
A cow wash.
How surprised was I to find out that those clever Germans have obviously been driving down far more roads than Jon and have a much lower tolerance of the dirty cow (or coo as it is pronounced here) and invented the Cow wash years ago!