Almost by definition these things are very difficult to predict. That’s life!

The question is: what’s worth very little now that will be worth millions in ten years? Presumably at any given point in time there exist such things.

True. I have no idea, not even a clue where to start looking for such thing. It seems to me that the best one can do is just diversify, acquire a bunch of stuff that might grow and hold them for 20 years.