I'm a bit of a sucker for a good movie intro. I don't really care whether it's artistic or crass if it's well made I will generally sit through the rest just based on a good first impression.
I'll give a handful of ones I can think of off the top of my head to start off, hopefully others can share their favourites.
Dead or Alive (1999) [nsfw?]
Lord of War (2005)
Blue Velvet (1986)
I'll give a handful of ones I can think of off the top of my head to start off, hopefully others can share their favourites.