"Who's there?!" I called back to the voice outside my door.
"A big crate filled with $18 billion in $100 bills, all for you!"
This is great! I thought to myself as I walked to the door. Now that I have $18 billion, all of my financial worries are over. I can live quite comfortably on $18 billion, and have some money left over to help other people!
But when I open the front door, I saw no big crate, and no money anywhere. Someone had played a cruel practical joke on me, making me think that suddenly I was worth $18 billion!
But then I said to myself, Wait a minute! $18 billion in $100 bills?! That would weigh almost 200 tons! And stacked neatly, it would be 15 feet long, 20 feet long and 20 feet high, give or take!
Pffft, yeah! I'd like to see a crate THAT big! I'd like to see the truck that could carry a crate that weighs 200 tons! Yeah, whoever it was, that joker really fooled me, making me think there was a crate with $18 billion in it, right outside my door! Good one, joker!
And, hey, next time, don't try: "It's a somewhat smaller crate filled with $18 billion in large-denomination US bearer bonds!" either, because I happen to know that there are only about $100 million in US bearer bonds still outstanding!