8. Pigeon guided missileDuring World War II, Project Pigeon was American behaviorist B. F. Skinner's attempt to develop a pigeon-guided missile.
The control system involved a lens at the front of the missile projecting an image of the target to a screen inside, while a pigeon trained (by operant conditioning) to recognize the target pecked at it.
As long as the pecks remained in the center of the screen, the missile would fly straight, but pecks off-center would cause the screen to tilt, which would then, via a connection to the missile's flight controls, cause the missile to change course.