Rats make a good pet. They are calm, friendly and smart and don't smell as much as mice. While wild rats from Norway were domesticated a long time ago as lab animals, their descendants today are smaller and calmer. Rats do not just have to be white. There are some rats known as “fancy rats” that come in a wide range of colors. Make sure you get a young rat so you have a better chance of training it. Rats are very smart and can be trained to be with you. They can travel with you in your sweater or pocket, and come when they are called.