The price penalty for the added complexity of a hybrid drivetrain has always been a bit of a concern for those looking to not just save fuel, but to save money. In some calculations from a decade ago, popular hybrids would have taken as much as eight or ten years to repay in fuel savings the cost of the car over an equivalent non-hybrid model. But today's fuel prices are closing that gap - in some cases down to just 18 months.

In the United States, $4 per gallon gasoline is a nightmare soon to be lived, though Europeans and others are already seeing prices double that amount, or more. But even at the relatively low fuel prices in the U.S., hybrids are seeing their payback terms drop to shorter and shorter periods.

For example, Toyota's Prius earns back the $3,489 cost above a similarly-outfitted Camry LE in about 3.5 years, according to Edmunds. Of course, that assumes 15,000 miles driven and fuel prices at $3.61 per gallon. Drive more or less and you could see the recovery period shorten or lengthen, respectively.

Milder hybrids, like GM's Chevrolet Malibu or Toyota's Camry Hybrid, with their smaller cost premiums, recover the price gap even quicker than the Prius. The $889 premium on the Camry Hybrid is erased in just 18 months of driving at the rates above. The Malibu takes a bit longer, at 2.7 years, but the premium is just $438, showing that in the Malibu's case, the hybrid option saves very little fuel over the already fairly efficient standard engine.

Some hybrids just don't offer much in the way of real fuel savings - so even though their premium over the standard car is not terribly high, it still takes a long time to recover the money initially invested. The Saturn Aura hybrid, for instance, only offers a 2mpg bump over city and highway figures for the standard Aura, but costs $3,595 more, which ends up taking over 16 years to recover.

At the upper tier of the market, where Lexus's luxury hybrids live, the cost calculus is still pretty nonsensical: a Lexus 600hL requires a lengthy 68.6 year payback period to cover the $18,630 premium.