How about a mouse, that our kittycats can follow for a brief time.
It would give the illusion of hunting. Perhaps the mouse can hide in a small log, or even a fake mousehole that we can put against a wall. The kitties can go to it, lie down, and watch the mouse for awhile, then get bored and go back to the usual wander, sit lie down patterns that are already built into them.
Please please?