Psychological thrillers

[Chris]

Im looking for things that mess with my head more than try to scare me.

Donnie Darko will mess with your mind, I still have no clue what it is really about.
http://en.wikipedia.org/wiki/Donnie_Darko
http://www.imdb.com/title/tt0246578/

As for psychological thrillers:

A Clockwork orange is a really weird film the last half an hour is "unusual"
http://en.wikipedia.org/wiki/A_Clockwork_Orange_(film)
http://www.imdb.com/title/tt0066921/
The grudge is another random film that will scare you
http://en.wikipedia.org/wiki/The_Grudge
http://www.imdb.com/title/tt0391198/
The suicide club would be my final choice for the choices. Only watch it if you have nothing else to watch, it is a really weird film that will play with your mind.
http://en.wikipedia.org/wiki/Suicide_Club_(film)
http://www.imdb.com/title/tt0312843/