Ferret ball pit made from plastic Easter eggs. Or switch them with plastic balls.
You'll only need 3 things to put these DIY no-sew cat toys together!
Peek out. Duck back in, leap a bit, race out the other side. Hours and hours of ferrety fun!
Marshall Pet Products Pop-N-Play Ferret Ball Pit Toy at PETCO. But it would be way cooler to make it yourself