You can have a number of toys which will help keep the hamster stimulated and also encourage exercise. There are many types of toys ranging from blocks, to ramps, and everything inbetween. These are not critical, but are a good idea.
It is important to have hamster wheel, especially for a spoiled hamster that eats really well. They don't have to go out searching for food like they would in the wild, so they need some way to shed some weight. Lack of exercise can lead to one very overweight hamster.
Another popular exercise medium is the hamster ball. Proper hamster pet care does not require it, but it sure is fun watching them run around the house. Make sure you put them down in a safe area where they can't hurt themselves. I'm pretty sure a hamster wouldn't enjoy bumping along down a lengthy flight of stairs, or being pawed around by the family cat.
Try to keep an eye on them! :)
Food