Double, double, double!
What if we could fold paper again and again? How thick would it get?
Let us start with a piece of paper that is 0.1 mm thick, and keep folding it in half.
(Note: it is very hard to go beyond the 6th fold, just try it! But let us imagine we can.)
So (if we could physically do it) then 102 doublings of paper would extend beyond the observable universe!
In a way it is comforting that two things we understand (doubling, and the number 102) can reach so far.