I've owned dogs, cats, turtles, hamsters, birds, newts, frogs, lizards, spiders, various insects, and snakes. (So far.) They're all cool in some way, but of those dogs are my favorites, no contest. They are social creatures that you can interact with, even talk to, and have them respond in kind. Cats are probably second, but they're kind of assholes. They just want to be fed and scratched, then it's like, "Don't bother me, Human."