We covered this here a couple weeks ago. Here's the link.

When the leftist film maker Michael Moore used his publisher's plane on a recent book tour, for example, critics lambasted him for enjoying the corporate high life. The Hollywood activist Laurie David, the wife of Larry David of "Curb Your Enthusiasm," was labeled a "Gulfstream liberal" in an article in the latest issue of The Atlantic Monthly for condemning S.U.V. owners while flying around in private planes.

Arianna Huffington, a financial backer of anti-S.U.V. commercials, has also borne the brunt of criticism for traveling in a jet; and a supermarket magnate, Ron Burkle, is perhaps as well known for his eight-bedroom 767 as he is for the more than $1.5 million that he has given to the Democratic Party since 2000.

Republicans, of course, avoid the hassles of commercial flight at least as often as Democrats. The former chairman of Enron, Kenneth Lay, even flew on private planes to his company's bankruptcy hearings. But no one accuses Republicans and their wealthy supporters of hypocrisy, of being "Gulfstream conservatives.'' "Democrats get hit with a double whammy," said Bill Blomquist, a political science professor at Indiana University-Purdue University, Indianapolis. "It's not just expensive and indulgent. It's also somehow against the principles of the party."

David Horowitz, a conservative purveyor of the hypocrisy accusations, says that the attitude is "everyone should ride bicycles, but we'll take the jets."

"The schools thing is a good example of that," Mr. Horowitz says. "They send their kids to private schools, but they oppose vouchers."

The image issue, the disconnect between average Americans and the celebrities who claim to love them, starts with the sticker price. The smallest Gulfstream sells for $11.5 million. An entry-level 25-hour share of private flight time, at companies like New Jersey's NetJets, costs more than $100,000.

This is not the kind of travel available to "the lunch pail guy, or the person at the hair salon," says the Republican pollster John Zogby. "They'll never see it."

Then there's the criticism of the rich environmentalist who flies in a private jet to Sierra Club fund-raisers. A midsize Gulfstream 200 uses from 1,200 to 1,500 gallons of fuel for a cross-country flight, so if it holds four people, giving them the chance to stretch out on the leather sofas, each person would use about 350 gallons of fuel. That's 10 times the amount of fuel used per person by 130 passengers flying coast to coast on a Boeing 737-300.

It's also nearly the equivalent of driving a Hummer cross country, twice. Mr. Burkle's 767, if it carries eight people across the continent, would each use 1,000 gallons of fuel, enough for eight Hummer trips from southern Brazil to Dearborn, Mich

Mr. Burkle did not return calls for comment, nor did Ms. Huffington.

Ms. David, whose husband was a creator of "Seinfeld,'' also could not be reached for comment. Liana Schwarz, who works closely with her at the Natural Resources Defense Council, an environmental group of which Ms. David is a member of the board, said that she was out of town. Ms. Schwarz would not say if Ms. David used a private plane to get there.

As I mentioned here, a single one-way coast-to-coast in the Kerry Gulfstream V uses about 2,000 gallons of jet fuel, depending on many factors like takeoff weight, cruising altitude, winds aloft, air temperature, etc. That's more fuel than most families use in a year even if they drive SUVs. Shorter flights use even more fuel per mile due to the high consumption during takeoff and climb.