If the CIA's decision to spend $20 million to turn cats into field operatives seems at all strange to you, know that it was the 1960s: The agency was also attempting to deploy psychics, drug dealers, Mafiosos, and prostitutes. Operation Acoustic Kitty commenced when a veterinary surgeon placed a microphone in the ear canal of the first candidate, along with a radio transmitter at the base of the skull and a wire antenna concealed by the fur (see diagram, left).
The first operation entailed eavesdropping on two men outside the Soviet compound in Washington, D.C. The newly-minted feline operative was released across the street, and, while scampering toward the targets, was hit and killed by a taxi.
The Agency deemed the project complete failure and cancelled it, destroying most of the records. One item lost to posterity is the training, other than it was hard because the cats' hunger often took precedence over the mission. Also it's hard to train a cat.
Click here to see one espionage author's speculation on the methods the Agency may have used.
For more information on Operation Acoustic Kitty, check out the book Frankenstein's Cat.