It's not even that difficult. Here's how it works: First of all, it almost always starts with servers at restaurants because they have access to your credit card out of eyeshot. They have a card swiper that is small enough to fit in your palm, and they quickly swipe the card. The info on the card is saved to an SD card in the swiper. They give your card back to you like normal. THEN (and this is probably the step that makes it hard enough so that not everyone tries to do it) you either take the SD card and plug it into a computer and then use the info to buy things online, OR you have a card punch/encoder and you print/clone the stolen cards onto a blank. It sounds like these guys were just encoding the data onto gift cards and then laundering the money through greendot pre paid cards, but the guys I knew who did this would actually print out a card with your real name on it, but the number (and the money connected to the card) were someone else's. This way, if you are asked for ID you don't have to run for the doors. To make things even harder, some people would use a fake ID and have multiple of these cards. The only drawback was that they looked kind of bootleg and cheap. Most people wouldn't notice, but I could spot a fake card a mile away. The guy would drive the swiper down to NYC and come back with a trash bag full of formerly blank credit cards that he would sell for $50 each. It was kind of a crap shoot, because you could spend the 50 and end up with a cancelled card, or you could spend the 50 and end up with some rich guy's black card that he uses for travel and therefore doesn't notice a few hundred in a different city.