I have one...Hitler: The Rise of Evil. This is one of the most terrifying films ever made, showing how the Nazis gained power and what they did with it, including sending the Jews off to death camps and using gangster tactics on their rivals. The end of the film was nothing short of disturbing.

My first experience of The Exorcist was ruined because my parents forced me to watch some parody movie involving Leslie Nielsen a few weeks beforehand, and so the scenes that i was supposed to find frightening were massively de-sensitised because of that, which was probably their intention. I've never forgiven them since!

The first time i watched The Grudge (American re-make) i was frightened because i was sitting alone in the dark, i've watched it again since though and almost felt embarassed that some of the scenes managed to scare me. As a kid the main ones were definitely Child's Play and A Nightmare On Elm Street. Most recently Rec scared me in a way that no movie has done in years, particularly the final 15 minutes (if you've seen it then you'll know what i'm referring to), and The Orphanage had a fantastically creepy atmosphere throughout much of its running time as well.

This may not classify as horror movie terrifying, but when I was 12, I watched Casino secretly, and Joe Pesci's death in that movie and that entire sequence, left me scarred and terrified for days.

I hadn't heard of this one and looked it up on IMDB. There are two that fall into horror -- [REC] from 2007 and Rec a.k.a. Quarantine from 2008.

To which one were you referring? I hadn't heard of either and you've sold the movie; I want to see the same one.

Pretty sure he was talking about 2007. The 2008 one is called Quarantine in the US and probably everywhere else too.

Sorry, i should have made that clear in my post.

Definitely watch the original Spanish version (Rec), the American remake (Quarantine) is predictably woeful and inferior.

Hmm... a lot of films that scared me in my early-late teens was largely because it was the first time I was exposed to such movies. My parents didn't let me watch such stuff...I either saw them at friends houses or when I was old enough to see/rent them myself. Now I'm mostly too jaded.

As a mid-late teen:
--Alien (couldn't watch in one sitting, had to turn it off)
--Nightmare on Elm St1 (a few scenes anyway)
--A Hammer film called "Demons of the Mind" (freaky/surreal Brit horror affects me more than US horror)
--The Omen
--Jaws
--I'm sure there's more I just can't remember.

As an adult:
--Blair Witch. I rented the DVD knowing nothing about it. I spent most of the film in a constant shoulders-tensed-like-rocks mode. I think if I had known about the pre-release hoopla it wouldn't have affected me nearly as much.

Everything else might make me a little tense in spots, or has the "ewww that's really gross/sick" flinch/shock-factor (Saw1, Cube, most US horror), but doesn't scare/terrify me.

Thank you, sir. I hadn't even heard of Quarantine so my expectations for the movie from which it was torn are high. If those final 15 minutes don't scare the hell out of me I'm holding Patrick completely responsible.

Oh, who am I kidding? Champagne for everyone!

I just answered your question major, you should blame Harmonica if you hate it...like I do or I would if I actually seen either movie.

Be sure to let us know what you think of it, majoraphasia.

There was, I believe, a Twilight Zone (?) episode when I was a kid where all of these children had black fingernails and killed as in murdered adults when they touched them. Anyone remember this?

WEIRD! I think you're referring to a movie called The Children, from 1980. I saw it about a year back and thought "This must be a Twilight Zone or Outer Limits episode." No, it's a b-movie.

Briillliiannnttt....You NAILED it. I can remember my older cousin Shelly babysitting me and my brothers and saying something along the lines of "I probably shouldn't be watching this with you guys..." After it was over I found a magic marker, painted my fingernails black and scared the sweet fancy moses out of her.

Whilst I will be seeing this over the next couple of days i am reliably informed that it is terrifying.

Cannibal Women in the Avocado Jungle of Death

The Netflix write up
To avoid an avocado shortage, the government hires feminist anthropology professor Margo Hunt (Shannon Tweed) to find the man-eating Piranha Women tribe who inhabit the avocado jungle of Southern California. Assisted by a chauvinist named Jim (Bill Maher) and a dim-witted student named Bunny, Hunt must convince the tribe to move to Malibu condos. Meanwhile, Bunny's contemplating joining the Piranha gals -- but she must consume Jim first!

Rob

Completely off-topic, but this thread reminds me of this:

holy shit!

is it a comedy? please tell me its a bad comedy.
i feel like i have to see it.

i should have it by Tuesday from Netflix - I'll report back
Rob

Alien - The first movie that truly terrified me, I first saw it when I was 8. Dallas' death scene still makes me jump to this day.

The Blair Witch Project - Very bad idea watching it in the dark. This movie creeped the hell out of me, and by the end, it was unbereable. I ended up watching it from a distance, standing in a lit doorway, just cause it felt safer.

Hellraiser - Or actually, the third one, Hell on Earth. As a kid, Pinhead himself scared the living hell out of me, and he still creeps me out.

Signs - I was tense the whole way through, especially with the damn birthday party tape.

I watched the original Halloween this year for the first time... and even though it didn't scare me, I have to admit it's incredibly well made and does an excellent job of creating a horror atmosphere. I can understand how original audiences would have been scared shitless. (And it also proved to me that Rob Zombie's remake was garbage)

Oh, and Requiem for a Dream isn't a horror movie, but it shocked and terrified me more than any slasher film ever could.

Alien - Just watched it recently for the first time...not a good idea to watch late at night home alone when it's rainy out...I couldn't believe how much this movie scared me even now.

The Thing - By far the movie that has had the most lasting impression on me. Watched it with my dad when I was younger and it scared the CRAP out of me. Couldn't sleep for a couple days, nightmares about that dog creature thing...ugh. Even to this day I can watch it and it still gives me the genuine creeps. Awesome movie.

The Blair Witch Project - probably because I didn't expect it to be that level of terror. I watched it because of the pure interestingness of the concept. It built up and up throughout the movie. And the minutes since they enter the "house," I had silent screams over and over. Finally, the last some seconds of the movie make my legs and my feet go rigid like I was having a seizure. Never have I been that terrified.

REC is a good one too. The "attic" scene almost dislocated my heart from my body