Q WOULD have been proud: today’s James Bond operatives go nowhere without the latest gadgets to ply their trade, and that includes the oldest trick in the book: the dead letterbox.

Today it is called the EDLB — the electronic dead letterbox — a computerised system that enables secret agents and their handlers to swap information with none of the risks of handing over written material.

The Moscow EDLB would have been devised by boffins working at the joint MI5/MI6 technical services branch in Buckinghamshire.

It comes from the same stable as the “infinity device” — a specially adapted mobile phone that hacks into another cellphone, makes it switch on without triggering its display light and then converts it into an eavesdropping system.

Similar gadgets include the keystroke system, which is inserted into a target’s computer and then records everything sent and received. An eavesdropping system called TEMPEST enables an agent, sitting in a van in a street, to monitor everything being written on an unprotected personal computer.

The EDLB consists of a tiny computer capable of storing several megabytes of secret data hidden, in this instance, in a man-made rock. Using advanced wireless technology — WiFi or Bluetooth — a Russian agent needs only a hand-held computer and a password recognised by the hidden transmitter to “squirt” his secret files into the memory bank.

“He wouldn’t even have to know about the rock. All he has to do is go to a certain location and transmit his files, taking just a few seconds,” Nigel West, the spy historian, said.

The case officer, holding a similar computer, would then walk to the park an hour later, and with the same coded signal “interrogate” the hidden computer and download the latest “dropped” material.

The biggest risk comes when the computer battery needs recharging; then someone trying to look more like a geologist than a secret intelligence officer has to pick up the rock and remove it. The Russian FSB agency claims to have photographed a British “diplomat” doing just that.

The EDLB has come a long way. In the Cold War days dead letterboxes included hollow tree stumps, discarded tin cans, flower pots and loose-fitting bricks in walls.

Robert Hanssen, the CIA officer who spied for the Russians, used to put his secrets into a rubbish bag for collection by his handlers. Michael Bettany, an MI5 intelligence officer who spied for the USSR, taped film canisters to the inside of a lavatory cistern in a West End cinema.

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