Cats need stimulation that caters to their instinct for hunting and causing trouble for their human owners as often as possible. One unique toy that many cat owners and cats seem to like is a robotic toy that swishes a fake tail around in a circle underneath a plastic covering.
Cats can then practice pouncing on the mechanical tail as it swirls around. Of course if a cat catches it, it will likely wreck the toy within seconds but at least the cat may have been amused for a split second or two until you have to shell out more money to buy another toy your cat will wreck within minutes.