How to keep pigs entertained?

We just got a pot belly pig. She is a pet and we will not eat her... her brothers are a different story. When we leave during the day she is inside with our dogs and crated. What would be a good thing for her to keep her entertained while we are away. We currently are in a neighborhood that has an HOA so she can not be left outside while we are gone. We are hoping to get moved to an area without an HOA in the next 2 months so this won't be an issue. But in the mean time what are your suggestions?