Cats are nice and independent. We had a cat once that was actually trained to go outside instead of using a litterbox. Ticks me off though... the cat I have now likes to jump on the cord to my headphones and jerk my head down while I'm playing Counter-Strike.
I'm not allergic to cats, but a friend of mine is. The cats kept jumping up in his lap and making his yelp with frustration. To this day, we believe the cats were purposely trying to kill him.