Alrighty then, I have a few hollow things to share:

Kokee in the hollow between the sofa and the wall, hiding from thunderstorms.

My hollow strawberry pot.

Hollow dead Cholla cactus, Cholla skeletons I guess they are:

A solar powered frog light:

A hollow owl:

Some ground squirrels hollows:

This bunny has hollow ears. It was chewing on something stick like.