Gritty, great crime movie.  The writer, Troy Duffy, claims the story was inspired by real life events he saw while living in Los Angeles.  I don't know about that, but it does also star William Dafoe, who I am a big fan of.  I think I like any actor who is patently incapable of playing a romantic lead in a chick flick.  He was great in Mississippi Burning.  

This movie has a great cult following.  I think the popularity stems from the "everyman" taking out the bad guys.  The religious connotations are pretty cool too.  I just tried to find some cool site related to vigilante justice, but for the most part none of them really struck me as interesting.  Best thing I found was some article about vigilante gangs in Mexico, beating up robbers and kidnappers.  No that great, to be honest.