Useless Ball

My last model of 2025.It is a 3D shape I had in my head, so I decided to make it, but I have no idea what it could be used for.It looks cool when printed in multiple colours. The inner part is forever trapped inside the outer ball and jiggles when you shake it. Maybe it works as a cat toy? I will give one to my neighbour and see if her cat likes it.https://www.starryodyssey.com/design/useless-ball