My first hamster was nice. The last 5 were awful. AWFUL. Bit everyone, escaped, smelled. BLEH. Same for guinea pigs.
I'm not particularly fond of Guineas, or pheasants, quail, peacocks, or Exotic birds (The things are hateful and love to bite. Not to mention make a mess and smell). Actually, any bird besides chickens - they are the only birds that I love. Well, I do seem to get along with Canadian geese quite well but that's a different story.
Toy/small dogs. They aren't dogs. They are hateful, pushy, loud, aggressive, and high maintenance... things. I'm sure this doesn't go for all small dogs, but it does for all of them I've ever met.
Pigs. There is something about them that I just don't like. Never had one, never pet one, never really been around them. I just don't like them.