I don't know how many times I was ninja attacked by my cats when I would walk by a box, thinking it was empty and finding out the hard way that nope! - cat was in the box. Also don't know how many times I thought they were trying to kill me off and make it look like an accident when I would walk by a box and one of their (MY) balls of yarn would go shooting out of it at Mach 4 and I'd have to do some fancy dancing to avoid it or risk breaking my neck - LOL! An empty box on its side and a ball of yarn shooting out of it would probably be the death of me, but considering some of the animation I've seen, I think it's completely doable. Make it a neutral object so no decrease in happiness and every feline exhibit could have it.
I'm still dying laughing here, LOL!