The US PBS network's program Pet Tech featured Duncan, a virtual sheep dog who looks after a virtual flock. Created by a team at MIT's Media Lab, Duncan has a mind of his own and can learn to respond to verbal commands. Like a real dog, however, Duncan's performance often depends on the skill of his human master.
With advice from Gary Wilkes, they used a clicker to teach him a range of commands.
You can watch episodes of Pet Tech online.