superballs - yes! my dog swallowed one unbeknownst to my brothers and me while we zinged probably 10 balls around the house. a few years later after several bouts with not being able to eat, our dog couldn’t even swallow water and we had to take her to the vet. "There's something spherical blocking her stomach" was the news. Sure enough, they operated and removed the superball, with acid marks around the surface but it was still smooth and bounced like new. Our dog was like a pup again, full of energy. I say we remove from our existence all small round things that bounce.