In Trigun, Vash the Stampede is wanted for sixty billion double dollars ($$60,000,000,000). I don't remember any indication of how much money that actually is in the Trigun universe. I'm sure it's quite a lot, but how much is it really? Enough to buy a house? A power plant? An entire city?
So, how much is $$60,000,000,000 actually worth?
$60,000,00,000.00
is a variable that contains the variable with actual amount. You are extracting the value of it by prepending another$
. this is a variable variable... sorry, I'm from stackoverflow, so this was a joke :P