I lOVED [rec] but Quarantine, the American remake, just wasn't up to the same standard. I dunno if the fact it was foreign made a difference. I find a lot of Japanese stuff really scary - to the extent I refuse to watch Ju-On and Ringu, etc, as i found the Americanised ones too scary. I can't for the life of me think what other Japanese horrors i've seen but they're normally made by Tartan Asia Extreme - can usually tell they're gonna be frighteners if a film's made by them (I think they done Oldboy as well).
Its the bit in The Grudge (or Ring??) where the girl's found in the wardrobe at the very beginning, where her mouths all wide open and her eyes are all huge... Eeeek!!! And the little Japanese boy, and all the hair, and the jerky movements!!
Ooh that reminRAB me - in the film The Gift, there's a bit where Cate Blanchett is havin a kinda vision and there's a fiddler in the sea / river, and all of a sudden he starts playing his fiddle in a really jerky, fast motion - that scared be bejeesus outta me!!!