Any of the Old Boy/Sympathy for Mr & Mrs Vengence are good.
Ju-On (the original Japanese version if you haven't seen yet).
Jacobs Ladder (classic)
Takashi Miike is great - Check out The Happiness of the Katakuris for a classic if you can find it.
The Changeling (original). Although PG, still creeps the hell outta me
and of course Spinal Tap..