Natural Born Killers.
Almost all of the songs are excellent, and sound clips of the film integrated with the music actually give a pretty good audio summary of the film. Also, this album has amazing variety- Patti Smith to Leonard Cohen to NIN to...whoever sings the stupid rap and death metal songs towards the end to Juliette Lewis herself, this soundtrack manages to maintain one of the darkest sounds I've ever heard without sounding trite, whiny, or excessive.
"I'm thinking about leaving tomorrow
I'm thinking about being on my own
I think I been wasting my time
I'm thinking about getting out"