Have you seen The Machinist?

I watched this movie yesterday, and was expecting more than what i've seen. But to be honest with you Bale gives a performance that will resonate in my mind, that's for sure. Losing that much weight to play this role must have been grueling. His character is one that you like, pity, and don't understand
For almost a year, Trevor Reznick (Bale) has been unable to sleep. His body wilts away from the lack of sleep, making him look like a Holocaust victim. As his body deteriorates, his mind begins to follow. After an accident at the machine factory he works in (in which a co-worker loses an arm), he begins to receive notes from a mysterious person that jumps in and out of his life. The more he seeks to unravel the mystery of the man as well as his own life, the more the lines of reality begin to fade.
Have you guys seen this movie? What do you think about it?