Scenario
A shopper chats on his/her cell phone near a store's cash register while you pay for a purchase, or he talks on a cell phone outside a restaurant window while, just inside, you use your credit card to pay for a meal.
How It Happens
Though the bystander appears to be deeply engrossed in his conversation, he actually might be using the camera built into his cell phone to snap digital pictures of your name, your credit card number, and the expiration date. Some cell phones now contain eight-megapixel cameras, with sharp enough resolution to snap a legible picture of a credit card even from several feet away.
Self Defense
Be aware of people around you whenever your credit card is out of your wallet, particularly if someone nearby is holding a cell phone. Conceal your card under your hand, or at least turn the card over.