A Serbian Film didn't really phase me, still the way the baby cried in that scene kinda made me think maybe these guys know what it really sounds like, but other than that I just shrugged it off.
I've seen about 3/4 of the movies named here, August Underground is probably the only I had to pause,walk away, and stand outside and catch some air because I really couldn't stand it, I took about a 30-40 minute break in the middle of the movie just to catch myself, then got blown and finished it, killed my high though.
Also, someone mentioned Ichi The Killer, really? I thought it was hilarious.