Scariest movie you've ever saw and why

[Rosemary's Baby]

I sleep like the dead, so that can't be a factor. But, I've had a few that freak me out, for a short period of time. When I was little, it was Critters. Not the scariest thing in the world, unless you're 7. More recently, the creepiest thing I can see is a kid dying. Esp. since they use little blonde headed blue eyed girls often, which I have one of those. Then, it's not scared, it's more dread.