Cyborg Cat

Back in the 60's, when spying was all about telephones in shoes and knockout gas in wristwatches, the CIA came up with a crazy program: Operation Acoustic Kitty.
Yes, that's the real name.
They implanted a microphone microchip in a cat's ear canal, an antenna was embedded down his tail and a transmitter was implanted at the base of his skull.
... This cat was a literal cyborg kitty who was supposed to be able to just walk up to people and record their conversations.
The craziest part is that the whole project cost about $20,000,000!!