And, as Melinda Murphy reports on The Early Show, some have found a unique way to run their cars that costs practically nothing.
Dave Kandell is one of them. His car runs on grease — used vegetable grease, that is.
Instead of heading for the gas station when it's time to fill 'er up, Kandell makes the round of restaurants in Huntington, N.Y., picking up used fryer grease he gets for free.
Sal Pagnotta, who owns Rosa's Pizza, admitted that when Kandell first asked him for the oil, "I thought he was crazy. I thought he was lying to me!"
Even Kandell's mom wondered if he'd gone a little nuts.
"I thought," Bea Kandell told Murphy, "he is probably taking a lot of time that he might be able to do other things with that might be more profitable."
After a pause, she added, "But now, maybe he's onto something!"
He just might be, Murphy said.
Wally Little owns a service station called Wally's Super Service, and has converted hundreds of vehicles to guzzle grease instead of gas.