These pigeons have brain implants.
"Scientists with the Robot Engineering Technology Research Center of east China's Shandong University of Science and Technology say they implanted micro electrodes in the brain of a pigeon so they can command it to fly right or left or up or down."
So much for homing pigeons. Now that they come with remote controls, these flying rats could actually be useful. Just think of all the disease you could spread to your enemies! :-P