I'm a big fan of thrillers. Not only do I enjoy analyzing the plot, but I think being scared in a controlled and safe environment in important. I believe it teaches the mind to be prepared when the unexpected happens. I'm not saying you should be preparing yourself to be stalked by a psychopath, which often happens in thrillers, but if you witnessed an attack or even a car crash, your mind will likely not freeze up the way it would if you had never been exposed to violent or scary situations in a safe environment.