I'm a reading a book called "Spy Catcher" by
Peter Wright, who was the Assistant Director of MI5. Forget James Bond - MI5 had no business being in the intelligence business in the 1950s and 1960s. MI5 was completely penetrated by the Russians, and more people in MI5 worked for the Russians than did for the British government.
However, I found "
the thing" to be rather interesting. Basically a Russian youth group gave the US ambassador a large wooden plaque of the Great Seal of the United States - which he hung in his office. Although it was not powered in any way, it was possible to bounce a radio signal off of it - turning it into a microphone that could transmit voice. Neato.