There are more people than you would suspect with artificial eyeballs out there. 10% of all injuries are ocular, and it is estimated that as many as 1 in 24 people worldwide has a prosthetic eye. You would never notice though, because they are so lifelike, and few people with them will acknowledge it.

Higher-end prosthetic eyes use a magnet in the rear to "sync" with the other eye, so that they move in unison.