Where did the money go?

One of the big questions that arises from the current economic roller coaster ride certain parts of the community seem to be on is "Where did the money go?" With banks collapsing, investment firms being sold for a song, and homes being abandoned by people unable to pay them off, money that people believed was there seems to have disappeared. So who has it?
It turns out that my wife does. According to the receipt on the right, after purchasing 2 litres of milk, she received over 9 trillion dollars in change. Attempts by me to access some of that change have been unsuccessful however, as she claims she can't remember where she put her handbag.

(NB Identity of the store where she brought the milk has been deliberately obscured)