My indoor only kitty is getting up there in age, so he's not as playful as he used to be. But he does like to sit at the sliding glass doors (we have 3 of them) especially if the door is open and he can hear, feel and smell outside through the screen door. He does have a few cat toys, but I have to be careful that Zoee doesn't eat them. She's actually not as bad as DJ was about that.
And then of course we have the exercise track, which we commonly refer to as the hallway. Sometimes Taz likes to run back and forth down the hall. Eventually that ends up with Zoee chasing him though. But honestly, I think he likes it when she chases him. Shhh, don't tell him I said that.