What are some really good scary movies that aren't gory or gross?

The Exorcist is not that gorey. It has green projectile vomiting but that's about it. Oh, and the part where Regan is shoving the crucifix into her crotch. But you don't see it graphically, just a little blood on her nightgown. The scariest movie without much gore is The Strangers. It has just a little blood spatter on the wall. But it's very terrifying.