Help me in my quest.

Noroi, The Devil's Backbone, Begotten, Ouija (2007), Alone (2007), Jacob's Ladder, Ring (2002), One Missed Call (2004). . .

I second Jacob's Ladder. That movie is made purely out of mindfu'ck.
...
Also while Clockwork Orange has disturbing implications and socio-political themes.
I didn't find the movie actually scary.
That is almost like saying Children of Men is scary...