It's true - you really don't know what you've got 'til it's gone. In Aibo Sony created a pleasing novelty, a cute time-waster, and, we now realise, one of the most important robots ever to have padded the glob. This was a robot with a mind of its own, capable of reacting to or ignoring voice commands depending on its mood, and able to stalk your home or to frolic with its own pink ball before returning to its bed for rejuvenation. Through its three generations Aibo grew in functionality and intelligence, but Sony pulled the plug in March 2006. Happily, it's kept alive by numerous programmers, eager to eke extra cleverness and advanced behaviour from its envelope-pushing canine architecture.