9 The Grudge / Ju-On 
The Asian market exploded onto the scene in the last decade, producing a number of unforgettable films--the scariest of which was [Ju-On] was remade into the American blockbuster, The Grudge. The focus of both films is a curse that spreads "virally" amongst a web of unspuspecting characters who encounter those who have already been affected by the curse. The supernatural force at the heart of this film has one of the most memorable ways of announcing it's presence in horror film history [AaaaaaaHaaaaaaaHAAAAaaaaahhh!].
Both films are exceptional, but the Japanese version--while not as strong from a special effects standpoint--is superior in terms of fright quotient.