"The level of surveillance possible, not only by the government but by corporations and criminals as well, will be unprecedented. "When RFID chips are embedded in your ID cards, your clothes, your possessions, you are effectively broadcasting who you are to anyone within range," he said. "The dark side of RFID is surreptitious access," said Bruce Schneier, a security expert with Counterpane Internet Security Inc. Hackers could disable a car's RFID anti-theft feature, swap a product's price for a lower one, or copy medical information from an RFID chip. However, hackers and analysts are exposing potentially serious problems. The next generation of passports and credit cards are hotbeds for RFID. RFID chips, injected under the skin, can store a medical history or be used to control access to secure areas. Many of us start our cars using RFID chips embedded in the ignition key. Today, it can be used to identify missing pets, monitor vehicle traffic, track livestock to help prevent disease outbreaks, and follow pharmaceuticals to fight counterfeit drugs. So why is it getting so much attention now? The short answer is that RFID has moved into more common corners of society. The technology has been around for decades - the British used it to identify aircraft as friend or foe during World War II, and factory warehouses have used it more recently to make shipping more efficient. RFID sounds futuristic: A transmitter smaller than a dime embedded in everything from a T-shirt to human skin, communicating data over a short distance to a reading device. (CNN) - Radio frequency identification has been heralded as a breakthrough in tracking technology, and denounced as the next Big Brother surveillance tool.