In no particular order: 
1) Sleepers (1996)
2) The Last House on the Left (2009)
3) Funny Games U.S. (2007)
4) Audition (1999)
5) The Experiment (2010)
6) An American Crime (2007)
7) Straw Dogs (1971)
8) Hostel (2005)
9) Eden Lake (2008)
10) The Hole (2001)
11) I Spit on Your Grave (2010)
12) The Strangers (2008)
13) Irreversible (2002)
14) The Girl Next Door (2007)
15) Precious (2009)
16) The Human Centipede (2009)
17) Open Water (2003)
18) Dancer in the Dark (2000)
19) A Serbian Film (2010)
20) Martyrs (2008)
Spotlight on Film 
Completely agree with some of these, but some were superb and rewarding, worth the disgust ! Martyrs is really underrated IMO so is Irreversible. Love Dancer in the Dark.
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Great list – totally agree about Sleepers. I think people would pick it up just because of the cast, but there really does need to be a bit of a cautionary note before watching. Great film though and worth the watch, just don’t let the fabulous cast stop you thinking about what the film is actually about.
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Great list. Irreversible is definitely one i couldn’t watch again. I think that perhaps the German version of funny games is perhaps more traumatic that the US version though, a little grittier. The worst film i’ve ever seen (I wish I could unsee it) is called August Underground’s Mordum… truly awful!
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Thank you. Now I am looking at my list and don’t see ‘Salo’, that film at least deserved some kind of a honorable mention… I have not seen the German version of ‘Funny Games’, I should check it out – as German version of ‘The Experiment’. ‘August Underground Mordum’? Thanks for the suggestion, that would have probably gone to the very top of my list because I am feeling ill just by reading the film synopsis!
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Haha! Don’t watch August U. Mordum, it’s vile. I have a strong stomach and I couldn’t sit through it all!
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I’ve seen 9/20 of these films. I agree with most of them, particularly A Serbian Film, I Spit on your Grave, Hostel and Human Centipede. All really disgusting films that I’ll never see again. I have seen The Strangers a couple of times though. It’s very creepy but I don’t think it’s shocking enough to avoid watching ever again. I thought it was a pretty good horror. Great list overall.
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Thank you, much appreciated. I guess I’ve had some “personal issue” with the Strangers…I always find it a truly horrifying situation where total strangers target, creep and attack someone absolutely senselessly…
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