All rats should have a free range area. Even if your rats have a large cage it is important for them to have time outside the cage to run around and socialize with you. This page provides some ideas of what to put in your play area, where to set up.
Dime Rats and Accessories Look at that little guy in the middling of the cage imploring you to love Him! Materials: Premo Polymer Clay, Sculpey Gloss, C. Tiny Cage and Three Dime Rats~ Cookie Commission