Play on Hard, and wait until you get to the later levels. Like I said, it's not scary so much as it is stressful.
There's this one part I remember where you take an elevator downstairs, and right when you get off, there are these two angry moaning zombie things, and they come running at you, and you shoot them into pieces, but the pieces start going apeshit and crawling all over the room and you're running and setting them on fire but no matter what you do they tear your face off. It took me around 15 attempts to get through that part with limited ammo, and when I was done I felt like I had just been physically and emotionally abused.
Still great, though. And I agree about Tron's vagina.