If there's a silver lining to recessions, it's that things get stupidly cheap. And I'm not just talking about stocks; I recently booked a round-trip flight from Los Angeles to Washington, D.C., for $206. Bargains are everywhere you look, which can be a boon for consumers reaching for relief. It's like a stimulus package you never hear about.

This is especially true with regard to gasoline. Last summer's voyage to $4 gas, followed by a nosedive to less than $2 a gallon, created a massive stealth stimulus package for consumers and businesses.

Just how massive? I consulted data from the Energy Information Administration to get a better understanding. Using a few (admittedly cherry-picked) dates, here's the difference in the daily cost of nationwide gasoline consumption:

Date

July 2007

July 2008

December 2008

March 2009

Gasoline Consumed (gallons per day)

405 million

381 million

375 million

372 million

Nationwide Average Price per Gallon

$3.05

$4.05

$1.65

$1.89

Total Price

$1.23 billion

$1.54 billion

$617 million

$702 million

These are staggeringly vast savings. The difference between what we spent on gasoline last summer compared to this spring is roughly $840 million a day. Annualized, that's $306 billion a year, or nearly half the size of both the TARP bank bailout and President Obama's multiyear stimulus package.

Of course, gasoline is simply one byproduct of oil. When we broaden the scope to crude oil in its entirety, the savings are even more impressive:

Date

July 2007

July 2008

December 2008

March 2009

Barrels of Oil Consumed per Day

20.7 million

19.4 million

19.2 million

18.7 million

Average Price per Barrel

$73.44

$135.55

$38.73

$42.91

Total Price

$1.52 billion

$2.6 billion

$743 million

$801 million

The annualized difference between what we spent on oil last summer compared to this spring is $657 billion per year. That's almost five times the market cap of either Google (NASDAQ:GOOG) or JPMorgan Chase (NYSE:JPM), and more than the entire GDP of Saudi Arabia, Norway, Taiwan, New Zealand, or Switzerland. If continued long enough, the effect of oil's nosedive could be on par with any government-administered stimulus package to date.

Don't start screaming "green shoots" just yet
But as you've probably noticed, oil and oil products are starting to spring back in a big way. Oil has nearly doubled in price since January, and gasoline has surged about 50%. Some of this rise might be independent of an actual economic rebound, since supply cuts and investment cancellations by OPEC and private energy companies can (and probably will) overshoot. We had a demand bubble last year. We could just as easily have a supply antibubble going forward. Both push prices higher. Neither is very fun.

And while the likes of ExxonMobil (NYSE:XOM), Chevron (NYSE:CVX), and ConocoPhillips (NYSE:COP) welcome higher prices, those hikes quickly offset the stealth stimulus package that has saved consumers billions of dollars. Gasoline, for example, has surged by almost a buck a gallon since December. Assuming consumption stays flat, that could suck roughly $123 billion a year out of consumers' pockets on an annualized basis.

That's where things could get dicey, especially when it comes to consumer confidence. You see, the effect plunging gas prices has had on consumers -- while massive in dollar terms -- probably wasn't appreciated as much as it should have been. Why? Because wealth destruction in housing and the stock market has eclipsed its benefit. The joy of cheap gas shrivels when headlines remind us of ravaging unemployment and the meltdown of Citigroup (NYSE:C) and Bank of America. (NYSE:BAC). No one cares about the garden when the house is burning down.

Stealth stimulus, flagrant hindrance
Not surprisingly, these forces don't work the same way in reverse. While lower gas prices were largely ignored as something we deserved -- if not considered insignificant in the grand scheme of things -- consumers will doubtlessly feel that higher gas prices are an infuriating obstruction to economic recovery. People will feel nickel-and-dimed. They'll be upset. They'll lose confidence. This is a common theme in behavioral economics, where losses are substantially more painful than gains are pleasurable.

If economic recovery is met with an equally challenging bout of inflation, this subject will be of top importance in the years ahead ... and not in a good way. But hey, I guess that's just life for a country (still) heavily addicted to oil.

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Fool contributor Morgan Housel doesn't own shares in any of the companies mentioned in this article. Google is a Motley Fool Rule Breakers selection. The Fool has a disclosure policy.