My wife and I (we are both Brits) were driving in the middle of nowhere in Washington state. We stopped at a garage to get petrol/gas and discovered that the credit card machines in the unmanned gas station only seemed to accepted credit cards issued in the US - IIRC the PIN equivalent was a US zip code. Our personal credit cards (UK cards) and cash (no teller) were thus useless. Luckily my wife had a corporate credit card issued in the US that we were able to use, on the principle that she could ask for forgiveness from her company when we got back.