According to the U.S. National Debt Clock, our government is currently 9.371 trillion dollars in debt. Just how much money this is is actually pretty interesting.
I emailed Steven Levitt (of Freakonomics fame) for a rough estimate of how much (at current prices) it would take to purchase every economic right in the world-- i.e., how much money every sort of thing, property, and salable right in the world is worth. Now, this is back-of-the-envelope math, so there are plenty of caveats, but Levitt suggested the following as a rough estimate:
WDP (World Domestic Product) * 30.
Now, since cia.gov says the WDP as of 2006 (purchasing power parity) was estimated at $65.95 trillion, we get:
So, bottom-line? Our national debt is roughly equal to half a percent of the economic value of everything in the world. 1/200th of Every. Thing.
(Until we start to inflate it away, of course!)