I love the Interweb!
Plagued with solving the puzzle of figuring out how many plastic playpen balls will be needed to fill the kiddie pool we are using for a treasure hunt at work in a few weeks, I was once again reminded that Google is the provider of all things info.
I found this. An online calculator that will show you how many playpen balls it would take to fill an apartment.
From desired packing density, to number of balls to cost to fill the room. While not nearly impressive as the amount shown in the diagram - I now know that I need only 200 playpen balls to do what I need to do.
Random - yes. Useful - yes, yes! And to boot, the cartoon that inspired the development of the calculator - also fun.
Cartoon courtesy: xkcd