ok, so forget the box = smokie thing for now. Think about this: Are Nikki and Paulo, the Adam and Eve bodies in the caves?
If we go with this eternity theory, if would suggest all times existed within the same vicinity. Past, present, and future are all overlapping on the island. Look at this: Mittelos is an anagram for Lost Time. If you play the Karl Brainwashing scene backwards, the voice narrating the video repeats "Only fools are enslaved by time and space". Don't believe me? Check it out for yourself.
LOST - Be Kind, Rewind
So, my next point: The little black bag, that contained the diamonds, is the same little black bag that contained the black and white stones. And the producers said that Nikki and Paulo would become iconic.
Furthermore, this point was suggested to me by a friend. The producers WILL be addressing the tsunami of 2004. Locke, tells Paulo in this episode that "things don't stay burried for long". If time overlaps, what if it is the tsunami that caused the Black Rock to be pushed inland, and also causes Nikki and Paulo to be dug out of their graves and forced inland as well. And what if, someone finds them, some last survivors, and lays them to rest there in the cave.
Think about the black and white stones. Nikki, wanted the stones for herself, embodies greed. Nikki = black. Paulo, wanted to hide the stone in order to preserve Nikki's love for him. Paulo, = white.
What do you think? I suppose it could also be like, Jack and Kate laid to rest or something, but I can't think of any other way in which Nikki and Paulo would be "iconic", as the producers put it.