Acoustic Kitty was a CIA project launched by the Directorate of Science & Technology in the 1960s attempting to use cats in spy missions, intended to spy on the Kremlin, and Soviet embassies. A battery and a microphone were implanted into a cat and an antenna into its tail. This would allow the cats to innocuously record and transmit sound from its surroundings. [..] Surgical and training expenses are thought to have amounted to over $20 million.
The first cat mission was eavesdropping on two men in a park outside the Soviet compound on Wisconsin Avenue in Washington, D.C. The cat was released nearby, but was hit and killed by a taxi almost immediately. Subsequent tests also failed. Shortly thereafter the project was considered a failure and declared to be a total loss. The project was cancelled in 1967.
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