EASYCHAIR – also written as Easy Chair or EC – was the codename of a super secret research project, initiated by the US Central Intelligence Agency (CIA), aiming to develop covert listening devices (bugs) based on the principle of the Resonant Cavity Microphone – also known as The Great Seal Bug or The Thing – that had been found in 1952 in the study of the US ambassador’s residency in Moscow, hidden in a donated wooden carving of the Great Seal of the United States.

Upon discovery of The Thing, many US agencies – including the CIA – investigated the possibility of using the new – hitherto unknown – technology to its own advantage. The secret research took place in the Netherlands at the Dutch Radar Laboratory (NRP) in Noordwijk.

source: grugq