If you want an extremely easy, clean, no fuss pet that is an attention getter and a conversation starter, Madagascar Hissing Cockroaches are an excellent choice.
Shortly after recieving them, my nephew let one of them loose in my house. Three months later she came waltzing down the hall. When I put her back in with her comrades, within two days I noticed the substrate moving. Apparently little Miss Escapee was pregnant and came home to have her babies. Not many survived, as is the way of nature, but it was interesting to see the perfect miniatures come up out of the dirt.
They are the easiest pet I've ever owned. They are not at all messy and I've only had to clean them twice a year for the entire time I've owned them. They live in a 10 gallon fish tank with a secure screened lid. Note: They can climb glass and can escape! If that bothers you, use a line of vaseline smeared along the glass the whole way around and they won't be able to go any higher when climbing. You can also place a piece of tulle on the top of the tank, then the lid, and it helps dissuade them from an escape attempt. While they do have jaws, and I've heard them chewing on the metal screen, never have they attempted to bite me.
One thing I must put out there, these cockroaches are NOT the kind that dirty apartments and cities have. Madagascar hissers are fruit-eating bugs. They are used to living in high humidity and on the forest floor eating dropped rotting fruit. Mine are sweet fiends, but they will also eat pretty much any fruit or veggie you put in with them. Their absolute favorite was sweet summer corn. They don't need constant supplies of food, they can go a few days to a week without food. I do, however, keep them with water at all times.
I don't know why, exactly, but about four years ago I decided I needed pet bugs. I did my research on exactly what I was looking for and I was matched up with Madagascar Hissing Cockroaches.