Raccoons

They're probably really fun pets because of their intelligence, but they're nocturnal, so they get into all sorts of trouble when you're sleeping. I used to work with someone who had one as a pet, and she mostly loved it, but she sometimes wanted to shoot it. She definitely didn't seem to have the same sort of bond with it that you would form with a dog. I guess her relationship with it was like a relationship with a semi-psychotic cat. She ended up needing to crate it when she left the house because it was literally tearing her house apart. That's not good for the animal, since they're not content in there like dogs are.