First time I watched it I was tripping balls. When the dude in the beginning gets gutted I thought it looked like 1000 aborted babies, and the rest of the movie was absolutely awesome/funny.

I then saw it sober with my mom, and still thought it was fucking hilarious.

my .02sp

Edit:

I caught some of the parodies of stars (like Jack Black being kinda like a Robert Downey, Downey being Russel Crowe) But i couldn't place all of dem.