(CBS News) The federal debt is now about $16 trillion.
However, billions of tax dollars are sitting in bank accounts, doing absolutely nothing, according to a congressional report.
It's called "Money for Nothing," and it adds up the staggering amount of funds allocated by Congress but never spent on their intended purposes -- in fact, not spent at all, and tied up somewhere in bank accounts.
So while there are plenty of things for which the money could be used, it's languishing in forgotten federal bank accounts.
The report was compiled by the office of Republican Sen. Tom Coburn, of Oklahoma.
"The money gets granted, doesn't get spent; it's way past the time event on when the original grant was applied for," he explains. "They never close out the grant, they never bring the money back. It's just sitting out there in limbo."
Unspent tax dollars might be good news if they were returned to reduce the debt or deficit. But often, the spending laws require the money be maintained in accounts at taxpayer expense -- whether it's ever used or not.
For example, back in 2005, Congress set aside tax dollars for a futuristic magnetic levitation train across the Mojave Desert, to Las Vegas. But a series of technical errors caused so many delays, supporters abandoned the project. The $45 million for it could sit around forever.
There are many reasons so much money goes unused. But Coburn says a main reason Congress doesn't fix it is that there isn't enough support in either party to claw back the idle money.
"I could write a bill that would get all of that money back," Coburn said. "The question is, it would never get to the floor. ... They don't want to fight the political battle of saying, 'He gaveth and he taketh away.' They don't want the negative press."
In 2010, Congress set aside tax money to help 30,000 unemployed families avoid foreclosure. But the program ended with $568 million left over.
TARP (stimulus) money allocated back in 2008 to help homeowners fight off foreclosure is still sitting around four years later: $34.6 billion of it.
One-in-four of the nation's bridges is dangerously deficient or obsolete. Yet, $13 billion in federal funds earmarked by Congress for highway projects sits unspent.
Democratic Sen. Mark Warner, of Virginia, is also concerned. This week, he's pushing for a law called The Data Act, to give Congress a better handle on what's been spent and show, in real time, when money's sitting around.
"Where the money is not being spent well, where there is not accountability, we need to either pay down the debt or we need to use that to consolidate (it) into those programs where we're actually getting good value for our dollar," Warner says.
Not a good value, according to the report: an Olympic-sized blunder in Atlanta, with $2.7 million left over from an earmark for the 1996 Olympics -- money that, by law, could be spent "only on an event -- that ended more than 15 years ago."
The General Accountability Office recently found a billion tax dollars sitting in expired federal grant accounts alone at the end of last year.
The Office of Management and Budget says it's reviewing and streamlining its policy guidance on federal grants.
To see Sharyl Attkisson's report, click on the video in the player above.