Mice are tiny, curious, and social, traits which can make them the perfect pocket pet for people with limited space and budgets. The House Mouse, Mus musculus, has been domesticated for hundreds of years, allowing breeders to develop a large number of so-called fancy mice which come in a variety of coat textures, patterns, and colors. You can find anything from a curly-haired "Texel" to a completely bald "Hairless" Fancy Mouse, and there are a number of groups you can join that are dedicated to developing prize-winning exhibition-quality Fancy Mice.

In addition to the House Mouse, there are around 40 other species in the Mus genus, as well as a number of other more distantly related mice. Some of these undomesticated mice do make their way into the pet marketplace from time to time, especially the tiniest species with a cute appearance, like the African Pygmy Mouse or Europe's Harvest Mouse.