Kalifornia came out in 1993, just as 3 of the 4 lead characters were up and coming to the levels of fame they now possess in 2006. This is a nice psycho-thriller that should appeal to all David Duchovny fans because of his dry and intelligent narratives that find their ways into his work, like with most of his episodes of the X-Files, Playing God, and Red Shoe Diaries.
People who were put off by the heavy southern accent from Brad Pitt and Juliette Lewis' characters obviously have never spent much time in the south. For every "Brian and Carrie" in the south, there is an "Adele and Early" and in 2006, that's the real horror of this flick.
Aside from that, I think the film was written with a cult film intention - like with Carrie's photography, it's not suitable for mass consumption. But if you have a copy of this in your personal library, I think it says something positive about your tastes for freaky movies.