Some other physical comparisons that could have been included are actually the size of stacking 400 million people on top of each other, how big that would be,

Some other physical comparisons that could have been included are actually the size of stacking 400 million people on top of each other, how big that would be, and also how much food they would eat in their lifetime, and how much oil and/or plastic goods they would consume. Other than that, I agree with a lot of the other comments here, big numbers are big. "I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space, listen..." - HHGTTG