I've loved this movie since 2001 and i've never left its side since. It was truly an amazing movie and i think it's really underrated in my opinion.
It stars Winona Ryder and Angelina Jolie (Don't let that put you off, Angelina is absolutely amazing in this and it's probably one of her best movies), as Winona's character Susanna is sent to a hospital to "get a rest" as she says, when she gets there she discovers that they're all in fact utter crazy
. Angelina's character, Lisa, is a tactless sociopath who intimidates most of the inamtes at the hospital, Brittany Murphey is also in this, she plays a girl named Daisy, who's father appears (i say appears because it's not made clear) to be abusing her. The movie mostly centers around Susanna as she comes to terms with her new surroundings and also her "issues" with life.
It may sound really depressing, but it's a very powerful movie
. Did i also mention that Whoopi Goldberg stars as well?
If you haven't seen it, then check out the trailer and search it on amazon
It's amazing 
http://www.youtube.com/watch?v=U4-GD1VqdOA
It stars Winona Ryder and Angelina Jolie (Don't let that put you off, Angelina is absolutely amazing in this and it's probably one of her best movies), as Winona's character Susanna is sent to a hospital to "get a rest" as she says, when she gets there she discovers that they're all in fact utter crazy
It may sound really depressing, but it's a very powerful movie
If you haven't seen it, then check out the trailer and search it on amazon
http://www.youtube.com/watch?v=U4-GD1VqdOA