RFID credit cards are taking the nation. Also known as Radio Frequency Identification, RFID for short, these cards allow you to make purchases with your credit card without even having to type in a pin number, swipe your card through a reader, or even sign for the sale. Instead, a coil radio transmitter insider your card—imagine how small it must be!—sends out a tagged radio signature, that then gets transformed by the way you move your finger over the card.

In essence, your personal way of "swiping" your card with your finger gives the signal a distinct "shape" that acts like an electronic fingerprint. In theory, no one else could have this electronic fingerprint. It’s not so much theory anymore. Some credit card companies are already experimenting with RFID technology. You can use them at gas stations, convenience stores, maybe even vending machines.

But is this technology as secure as all the experts say it is? It may be, but the thought of not signing for your purchase may make you have the heebie-jeebies. Also, usually with regular credit cards, the cashier is supposed to look at your card and compare signatures, to make sure you are you, each and every time you make a purchase. With RFID cards, you forgo this extra step of security.

Another issue with RFID cards, and one you won’t hear the credit card companies make, is that RFID cards make it possible to too easily to spend and drive up your debt. If all a person has to do is wave their card at the fast food restaurant, to get gas, to buy that expensive new flat-screen televisions set, then chances are they may start waving their card more and more. In the long run, that will make a ton more money for the credit card companies. But for the buyer, that could mean a long lifetime of living in debt.

Another potential issue with RFID technology is that it could be the next wave of the future for everything from passports to security to get into buildings. It could be used possibly to even track your movements throughout the day, the week, and the year. Just imagine—your car, every building that you enter into, your house, your work—all of them have RFID security technology. That makes for a chance for Big Brother to keep an eye on you. A scary thought, and pretty far-fetched, yes, but a possible reality none the less thanks to RFID.