I think mice and rats are cute, but I wouldn't have them a a pet. They gnaw, so have to be kept in a cage where they make a lot of jelly beans and which have to be cleaned frequently. When I first worked in the toxicology lab, the staff has a pet rat named Bubba. It was huge and his fur had yellowed. I think he lived to be 5 or 6 years old which is really old for a rat. Rules changed, though, a we couldn't keep animals in the lab (there were special rooms where animals were kept).