Mice?

Does anyone here own mice? I'm thinking of getting maybe just one little small mouse for my own. I hear they are very friendly if you find the right one, and very easy to care for.

I want a mouse because I want a pet I can just... leave be. I have a bird and a dog. A bird requires an incredible amount of care, love and attention. Their cage needs cleaning, fresh food (including vegetables that he refuses to eat...) and water sometimes multiple times a day, and lots of time together. A dog requires walks, lots of food and water, grooming, and all that stuff. I love both of them very much but some days I'm worn out between needy sqwaks and the whines of a begging dog.

Do mice require any maintenance? Are they friendly when you do interact with them? What kind of supplies do they need?