Liposuctioning unwanted blubber out of pampered Los Angelenos may not seem like a dream job, but it has its perks. Free fuel is one of them.

For a time, Beverly Hills doctor Craig Alan Bittner turned the fat he removed from patients into biodiesel that fueled his Ford SUV and his girlfriend's Lincoln Navigator.

Love handles can power a car? Frighteningly, yes. Fat--whether animal or vegetable--contains triglycerides that can be extracted and turned into diesel. Poultry companies such as Tyson are looking into powering their trucks on chicken schmaltz, and biofuel start-ups such as Nova Biosource are mixing beef tallow and pig lard with more palatable sources such as soybean oil. Mike Shook of Agri Process Innovations, a builder of biodiesel plants, says this year's batch of U.S. biodiesel was likely more than half animal-derived since the price of soybeans soared.

A gallon of grease will get you about a gallon of fuel, and drivers can get about the same amount of mileage from fat fuel as they do from regular diesel, according to Jenna Higgins of the National Biodiesel Board. Animal fats need to undergo an additional step to get rid of free fatty acids not present in vegetable oils, but otherwise, there's no difference, she says.

Greenies like the fact that waste, such as coffee grounds and french-fry grease, can be turned into power. "The vast majority of my patients request that I use their fat for fuel--and I have more fat than I can use," Bittner wrote on lipodiesel.com. "Not only do they get to lose their love handles or chubby belly but they get to take part in saving the Earth." Bittner's lipodiesel Web site is no longer online.

Using fat to fuel cars might be environmentally friendly, but it's definitely illegal in California to use human medical waste to power vehicles, and Bittner is being investigated by the state's public health department.

Although it's unclear when Bittner started and stopped making fat fuel or how he made it, his activities came to light after recent lawsuits filed by patients that allege he allowed his assistant and his girlfriend to perform surgeries without a medical license.