Vegetables. No, not those kinds of vegetables. These [http://en.wikipedia.org/wiki/Permanent_vegetative_state] kinds of vegetables.
My cat just went through something like this yesterday because I saved his life as he was dying. Had to put him down.
It's just so surreal to see this. He was just a breathing corpse--he had no personality or anything, and his temperature was slowly falling. He couldn't smell, taste, hear, see, or even feel anything, and walked aimlessly into walls and off edges.
The idea of vegetables always scared me, but holy shit once you've actually seen one. It's the last way I'd want to die.