I found this at Bed Bath & Beyond for $20. The cats love, love, love this. Mostly, they just sit and watch it and occasionally try to catch the “tail”. I have found our oldest cat Sadie lovingly sitting next to it when she wants me to turn it on. It takes 3 D batteries and you press a button on the top and it moves around in a random pattern. The batteries don’t last long and D batteries are not cheap but that’s my only complaint for $20.
They have it on Amazon for $23 here.