Webster has a personal trainer...kind of like going to the gym. It's called the Undercover Mouse and it runs on batteries, has adjustable speeds and basically is a maddening little mechanical mouse whose tail is the tease, that flits around under the yellow cover promising hours of cat and mouse games for any cat. Even Sidney, in the background is entertained! I turn it on and go about my business and Webster has his own source of entertainment. Ahhhh.