Project Acoustic Kitty was a bright idea by someone in the CIA during the Cold War, in the 1960s. I can only assume there were people in that organisation who had too much time in their hands. I think that was around when they were trying various bizarre ways to kill, or at least embarrass, Fidel Castro. Anyone who thinks the CIA is behind every conspiracy going in the world should read about some of these plots and decide if the CIA plotters are really that good.
Anyway... The plan was to wire a cat for sound. You could do all sorts of things with that. Like, listen in to conversations in your Cold War enemy's embassy. Just imagine it, sir! We can have this cat wandering around among the guests at a party, or maybe at a secret meeting, being stroked on the ambassador's knee. It can't miss, sir!
Someone obviously hadn't heard of the expression "like herding cats." That is, impossible - a cat won't follow orders and you can't make it do anything it doesn't want to do.
So they got this cat - a tomcat - and inserted a microphone, with an antenna in its tail. Training? You have to be joking! If the cat was hungry, he went for a snack. If a female wandered past, well, he was a tom. Dogs have masters, cats have staff.
Finally, they got him ready and decided to test him out, only to have him run over by a car on the very first day. An agent had to run over and grab kitty to retrieve the equipment.
So ended the one and only effort to use a cat as a spy.