For the fans of rape there are a couple good ones that haven't been mentioned.
Netflix Instant has one called The War Zone where a girl is anally raped by her father. The daughter is smoking hot and the scene is very disturbing.
The other one is a movie called I'll Never Die Alone (I think). It's foreign and a group of girls are gang-raped in the woods. Here's the link...
http://www.megavideo.com/?v=OIQMGCOS starts at 30 min. mark.