As a matter of fact, you can. About two gallons' worth, anyway.

While it's nice to know that carmakers have thoughtfully built in this fudge room for the forgetful, it's actually part of a much more ingenious marketing strategy, according to Duchene.

"Gas gauges aren't linear," he notes. "They are set up so they actually stay on 'full' for a long time, mosey on down to half, then plunge quickly to about a quarter, then gradually make their way down to zero, at which point you have about two gallons left.

"So you feel good about your car because, when it's filled, it stays full for ages, which means you're getting great mileage -- you think -- and when you hit 'empty,' you feel lucky."

Martin advises against running on empty, however.

"What happens is, you can get a car to a point where it is starved for fuel and then it takes a long time to re-pressurize," he says. "You actually starve the injectors, you starve everything, and there's a better chance of vapor lock. When the light goes on, get gas, especially in the summertime."

-- Text by Jay MacDonald, illustrations by Brandy Kesl.