Fish (freshwater; I have Endler's and some killifish and cory cats, want a betta)
Snakes (I have a Kenyan sand boa, and I want a corn snake)
Finches (if I ever get an aviary set up)
Will not own:
Most small mammals (rabbits maybe, if I ever get to meet a ferret, they appeal to me too)
Primates (they freak me out)
Large wild mammals
Everything else, I don't have much of an opinion on.