Acoustic Kitty
Acoustic Kitty was a Central Intelligence Agency (CIA) project launched by the Directorate of Science & Technology in the 1960s, which was intended to use cats to spy on the Kremlin and Soviet embassies. In an hour-long procedure, a veterinary surgeon implanted a microphone in the cat's ear canal, a small radio transmitter at the base of its skull, and a thin wire into its fur.