European Union tax revenue authorities are on the alert for any infringement of complicated bunker fuel tax regulations. Turn the key of one of the big ones and 10 minutes later you will have spent hundreds of Euros - and that is without even moving from the spot. Add some cruising speed to it and you will be burning at least €2,000 an hour at average speed, based on the current price of diesel in France and Italy. Fuel is obviously the single most expensive cost item of running a superyacht. Little wonder the realisation triggers various behaviours down there in the Med, some just heady and erratic, others downright rum and perverse.