HaHa Yessss, I did that with a couple friends at a sleepover, and we nearly pissed ourselves.
We saw it again recently and had a good laugh about that.
But seriously I though that the exorcist was pretty effin-a scary for its time, the first time I saw the grudge I was pretty creeped for awhile but the second grudge is bullshit, The hills have eyes was just gory, One Missed Call Was only okay, All of the Final Destination movies should have there own genre: stupid bullshit, the Saw movies are cool but not scary, The Blair Witch Project was engrossing but not very scary, Cloverfield is actually one of my favorite movies, but thats just because its so funny (Insert part where bitchy girl explodes here), Paranormal Activity was okay, but not too scary,although I'm sure some people would disagree with me, and the new Friday the 13th was okay, but a remake.
All of which leads me to conclude that there are in fact no truly scary movies.
Except for Jeepers Creepers, Which is fuckin scary