Wham-O Bird
I still have a superball rolling around in a drawer somewhere. Like most kids back then, we all wanted to know what was inside that made it behave the way it did. But after opening up one that had cracked or otherwise been damaged, we found no guts inside. Unlike golf balls, which were always fun to crack open.
I never knew about the Wham-O Bird but I had personal experience with an identical item, possibly the same patent, but I'm pretty sure it was a foreign manufacturer. Instead of Wham-O Bird, it was called "Tim" and flapped around like a real bird. It made a racket but still got the cats into attack mode when it would fly around. I think these guys probably couldn't handle crashing into things so you had to be in an open area, otherwise one crash and you'd likely end up with something inoperable, from both the bird's perspective and the user's.
We have a "Wild Bird Center" store near us. I'll have to check and see if they have anything like this. If any retailer would have it on the shelves, they would be the one.