Interesting discussion about this topic from a Buddhist perspective. I've never really thought about it that much since becoming a Buddhist. In folk traditions in Europe, having déjà vu was a way of knowing something important was happening even if what happened was insignificant.
I have a friend who had it constantly and it freaks him out to no end. Sometimes it even freaks us out, not that he knows things, but because he strongly believes he has lived a moment in time that we are living now. But then again for us unenlightened beings, as mentioned earlier, we experience time as linear. But physicists have theorised that time is actually more like a dot on a piece of paper rather than a line, if it was drawn that is. Everything in time is happening altogether, rather than how most people different the past, present and future. Maybe when we become enlightened and directly realise emptiness, because we are so attained, we break free of seeing time as the past, present and future as in the linear model but see everything at once, like the dot on a piece of paper.
