Hmn... I've got loads, but I think the one that stands out in my mind is Ju-On: The Grudge. I first saw it when I was about 10, alone and late at night. Needless to say, after all the scenes of bloody ghosts crawling down stairs and appearing under bed duvets, I had many sleepless nights
It's also the film that sparked my interest in Japanese films, so bonus points for that
