I've just bought them last week.
If you have hamsters, you should try buying these colorful plastic balls. You can keep your hammies inside while cleaning the cage or anytime you like to play with them or simply just making them exercise more (good for the fat ones
Lol, I love to play sunflower seeds maracas (fill half of a small plastic container with the seeds and shake it, they love the sound) when they are in a ball and they'll race running toward me within the ball ofc. (The first one who touch my feet will get a seed!
When I'm painting at nights, I'd like to let them roam free in my working room inside the balls and when they have enough exercise (30minutes), they'll usually will bump the balls on my feet. They need some rest in their cage for pee & carrot eating before the next round... So many dramas you can see when they roll inside the balls, like when both or 3 of them get stuck in the corner... lol, traffic jam!!!
I have made some border now so that they won't get stuck in any corners...
My dog? She really likes following the ball, no pawing ofc. It's just that when the balls move toward different directions, she'll get confused which one to follow though.
Try buying some for your hams, it'll be fun! More hamster photos: [link]