"A Bittersweet Life" is crack. It's a Korean mob flick by the same guy that directed "I Saw The Devil".
"The Chaser" is a Korean flick about a corrupt cop/pimp hunting a serial killer. Straight

status.
"The Man From Nowhere" is basically a Korean version of American movies like "Taken" or "Man On Fire". If you like those kinds of movies, you'll love this one.
"Lady Vengeance" is a Korean movie by Park Chan-wook, the director of "Oldboy". If you liked "Oldboy" and "I Saw The Devil", you'll like this. It's another crazy movie about revenge, specifically the price of revenge, kinda like "I Saw The Devil". It turns you into a monster.
"Confessions" is a Japanese movie about a school teacher and the murder of her 3 year old daughter. Again, if you like them crazy ass Korean revenge movies, this one is

especially the 2nd half of the movie. It starts off slow but trust me.
"Stoker" is an American movie, but it's by Park Chan-wook, so expect some crazy shyt. A girls dad dies under mysterious circumstances, her uncle moves in and....well, the less you know about the movie, the better. The cinematography for this movie is fukking incredible.
"High Tension". If you guys ain't seen this, you're losing. It's a French horror movie about a serial killer hunting 2 girls. That's really all I can say but trust me, it's not as basic as that.
EDIT:
[REC] is a Spanish horror film, it's the original version of the American movie "Quarantine". This movie is 1000x better than the U.S. version.
Fred.