Brother, can you spare a billion? More like $700 billion, to be precise.

With Washington trying to finagle a $700 billion rescue for the nation's financial system, the federal money sought by other projects is starting to look like chump change.

You could buy yourself a war with that kind of money — the U.S. has spent $648 billion on Iraq war operations so far.

You could match Franklin Roosevelt on his New Deal and raise him billions more.

Even in a town where billions come and go without anyone blinking, the money that could go into the Wall Street rescue is eye-popping. The House on Monday voted down a proposed $700 billion bailout package, but congressional leaders said they were committed to trying again.

What else could the government do with a $700 billion blank check? There are, well, billions of possibilities.

It could ensure universal health care coverage for six years, for example, or upgrade the country's most deficient bridges four times over. All the work to upgrade coastal levees that's been done since Hurricane Katrina? It's a mere drop in the proverbial $700 billion bucket — $7 billion, or just 1 percent.

You could build 1,750 bridges to nowhere.

Or run an entire country. Seven hundred billion dollars is more than twice the size of the economy of Denmark, which had a gross domestic product of $312 billion in 2007.

Seven hundred billion dollars would buy 70 Hubble-type space telescopes. Or about seven international space stations. It would finance the National Institutes of Health, the nation's premier medical research institute, for two decades. Or pay the U.S. national intelligence budget for 15 years.

According to the Wall Street Journal, half the money FDR spent on his New Deal program to lift the country out of the Depression and banking crisis was for public works projects. For $250 billion in today's dollars, the nation got 8,000 parks, 40,000 public buildings and 72,000 schools.

But that's thinking small.

Presented with the presumptuous question of what could be done if the government suddenly came into a spare $700 billion, scientist M. Sanjayan said he'd "re-envision how we live on the planet sustainably."

"Instead of bailing out corporations with $700 billion, we could be bailing out nature," said Sanjayan, lead scientist for the private Nature Conservancy. "We could fix all the harm we've done in the past but also get it right going into the future," in the ways that people get energy, use water and procure food. He's talking about everything from creating green jobs to boosting solar energy and protecting watersheds.

"I think you could do it for that kind of money," he said.

On a more mundane level, $700 billion could pay the wages of 22 million average Americans for a year. (According to the Labor Department, the average nonsupervisory, non-agricultural wage was $612 a week in August.)

You could even shoot for the moon. The Apollo program that put man on the moon in 1969 cost roughly $164 billion in today's dollars.

Truth be told, the government doesn't really have this kind of money lying around to spend hither and thither.

But there are plenty of other possibilities for the pondering:

—Seven hundred billion dollars would cover one year's health care bills for more than 85 million seniors, disabled people, children and low-income Americans enrolled in the two giant government health care programs, Medicare and Medicaid. This includes the elderly in nursing homes and many of the frailest people in the country, whose care is the costliest to provide. Adding another 10 million children to the State Children's Health Insurance Program, the subject of big congressional battles in recent years, could be done for the relative bargain-basement price of $35 billion over five years.

—The government could pay off the $550 billion in outstanding student loan debt in the United States, and then some. That's from both government and private lenders.

—Seven hundred billion dollars could cover the entire U.S. national intelligence budget for more than 15 years. Annual intel spending is about $44 billion, for about 100,000 personnel across 16 agencies; an armada of satellites and technical programs to collect electronic signals, environmental samples, imagery, computer and phone communications; and a small fleet of armed unmanned aerial vehicles, among other weapons. Intelligence is human-intensive work, however, so an infusion of a huge amount of money would have only limited utility without skilled people to transform collected data and information into "intelligence."

—Seven hundred billion dollars is five times what the federal government has devoted to Gulf Coast recovery in emergency funds and tax credits since Hurricane Katrina.

—Seven hundred billion dollars would allow the Pentagon to spend another seven years at war, fighting on two fronts, and still have enough money left over to cover the cost of the Army's annual budget of more than $140 billion.

—How about a state-of-the-art nationwide communications network for emergency workers? The Federal Communications Commission has been working for more than a year to create one, but Congress hasn't forked over any money for construction. Estimates of the cost range upward of $15 billion. Seven hundred billion dollars would buy a premier communications system. Actually, it would buy about 47 of them.