It is widely known that the NSA intercepts communications over the internet, but you may not have known the agency is spying on more than 100,000 computers that aren't connected to the net using radio technology.
According to The New York Times the technology, which is called Quantum, uses covert radio wave channels to transmit data to and from a targeted PC. A tiny circuit board or USB card dubbed Cottonmouth I must be inserted into the target computer, by say a spy or some insider, which then beams data back and forth to a suitcase-sized relay station manned by NSA agents. Experts say, many times these small USB transmitters are put in place before the equipment reaches its destination, at which point agents can access WiFi networks and retrieve and insert data as they see fit from up to 8 miles away.
The NSA is said to be making use of this technology outside of the US in places like Iran and China and to monitor Russian military hackers and other terrorist groups. In fact, it was used by the US to keep tabs on the Natanz uranium plant in Iran, which in turn spearheaded the US stuxnet computer worm initiative against the country.
The technology is said be a little out of date being that it requires some kind of physical interaction with the intended target, other techniques are being developed (like DROPOUTJEEP) and put to use that don't require this kind of potentially dangerous activity. Unlike the dragnet data collecting the agency is constantly accused of, technologies like Quantum actually appear to be of use when it comes to preventing terrorism and other horrible activities.