This is the sort of situation we all do our best to avoid, arrival in a foreign city at night, hours late after a cancelled flight, dreaming of a hotel bed, hopping in an airport cab and being driven round and round through deserted rubbish-strewn streets lined with rundown warehouses, rain pelting the windscreen, taxi metre rising as fast as the sewerage-filled canals, now it's midnight, now it's 1am, and still no sign of any hotel, driver behaving more and more strangely, and you're just waiting for him to park the car in some particularly dark alley where even the mangy dogs cower, bracing yourself for the struggle of your life.  But of course, the worst doesn't happen, and although the target cheap hotel has been long since forgotten in the driver's bid to empty the passenger's wallet, it's a relief at 1:30am to pull up at a five star hotel and think of the visa card in the money belt, and to remember that this is the exact situation credit cards were designed for.