Cheap gas has been an unexpected blessing to millions of American drivers. But will it last?

Chances are gas prices will eventually rebound above $3 a gallon nationally, though no one can say with certainty when that will happen, let alone how high they'll go.

Now drivers have a way to protect themselves against the threat of a sudden spike.

Enter LoveMyGasPrice.com, a service that launched last week allowing consumers to essentially purchase insurance against significantly higher prices.

Using the hedging strategies that large companies like FedEx (FDX) and Southwest (LUV) rely on, LoveMyGasPrice.com lets drivers put a cap on their monthly gas expenses. When prices rise above the capped price, customers actually get cash back.

This is a way to "take control and manage your fuel exposure," GP Manalac, who founded the company after creating a similar one in the electricity market, told CNNMoney. "This addresses a need that is not being met by the marketplace."

Related: Popular Google search: 'Why are gas prices so low?'

How does it work? Customers -- regular Joe's as well as businesses -- can purchase a gas insurance plan from LoveMyGasPrice.com for $3.99 a month. Currently, the plan caps gas prices at $2.75 a gallon, which is well above the current national average of $2.39.

If gas prices -- as measured by a government index of average retail prices -- climb above $2.75, LoveMyGasPrice.com promises to refund customers the difference through PayPal.

For example, if the gas price index rises to $3.75 a gallon for one month, drivers would receive a $20 refund for the month. That's the difference between their actual cost of $75 (20 gallons of gas at $3.75 each) and their capped cost of $55.

The LoveMyGasPrice.com cap in California is higher, currently at $3.75 a gallon. That's because gas prices in this state are sitting at $3.15 a gallon, according to AAA.

Related: Americans aren't spending their gas savings

Bracing for a price spike: Cheap gas is saving Americans about $750 a year, according to the government.

"Everybody got a windfall when gas prices started unexpectedly dropping like a rock," said Larry Weil, the company's chief marketing officer.

However, LoveMyGasPrice.com says that at least four times in the past 15 years national gas prices have jumped by between 50 cents and $1.10 a gallon in as fast as three months.

"It's going to go up. It's a matter of when," said Weil.

Right now drivers can only purchase a cap on the price of exactly 20 gallons of gas per month. That covers roughly two fill-ups for a typical vehicle. If they drive more than that, they can buy multiple plans for $3.99 each.

LoveMyGasPrice.com isn't the only player in this market. MyGallons.com allows customers to pre-purchase gas online and lock in the current price. That's very helpful if prices spike, though it could backfire if the opposite occurs.