Alien technology or future human technology that has somehow slipped time allowing us to see and use it. The island I mean, or Jacob, if you wish to call it that.

I'm going for future human tech, as in the Philadelphia experiment, only produced far in the future, and lost, first finding it's way to the Egyptians, who tried to use it, or at least understand it, then to the Mayans, eventually to the 60's, and American businessmen fronting colleges, ALL thwarted by a few who have lived on the island for as long as it's existed... led by the Not-yet-born, Richard Alpert(which is why he doesn't age, he isn't born yet).

The Others are not searching for a chosen one, they are searching for the creator of the island itself, who alone knows how to properly use the technology that has been manipulated since the first ancients found the island. The Others just want to get home, to their own time. any thoughts?

But I'll listen to those who have a theory that it's an alien ship covered in jungle vines!