Project Orcon was a WWII-era effort to find a non-jammable guidance system for missiles; pigeons were one of the things they tried. Loaded into a missile, the pigeons were to tap on the image of the target to correct the missile’s trajectory.
Trainee pigeons were started out in the primary trainer pecking at slowly moving targets. They were rewarded with corn for each hit and quickly learned that good pecking meant more food. Eventually pigeons were able to track a target jumping back and forth at five inches per second for 80 seconds, without a break. Peck frequency turned out to be four per second, and more than 80 percent of the pecks were within a quarter inch of the target. The training conditions simulated missile-flight speeds of about 400 miles per hour.
More information at Wikipedia, including some interesting see alsos: bat bomb and anti-tank dog. (thx, dan)