Scariest film ever made

Rating: 10/10 (2 February 2006)

OK, just a brief comment-- I saw this a few days ago at Sundance. I'm both a huge fan of horror films and a really difficult scare-- while I enjoy horror films, I frequently find myself disappointed in the actual scare department.
As far as I can think, I have never been more scared during a movie than this one.
I spent half of my time jumping out of my chair and the other half clutching my chest. People ran out of the screening because it was too scary for them-- which I don't think I've ever seen before (at least, not at Sundance). As a total claustrophobe, I thought it might have have just been targeting my weak points, but my boyfriend screamed about 10 times in the movie- a first that I can think of.
Afterwards, I said "This is probably the scariest film I've ever seen." He said, "Well, it's definitely one of them." "What have you seen that's scarier?" I asked. He couldn't think of a movie that came close.
And again, we watch a lot of horror movies. This movie is amazing.