Yikes . . . I just returned from 3 weeks in Florida, having made many stops for diesel fuel. A lot of the truck stops require that they "hold" your credit card while fueling. Several days after returning home, I received a new American Express card delivered by UPS. I called for an explanation, and they said that someone tried to charge using my account number (without physically having the card). Fortunately, it was not allowed to happen - the credit card company caught it. They suggested that "someone" likely copied the number on the credit card. Not sure what the answer is . . . just a head's up!