The Internet has helped consumers save money on various travel expenses: Bid down the price of a hotel room. Shop smarter for airline tickets. Make car rental companies compete more aggressively for your buck.
But when it comes to shopping for eons-old fossil fuel -gasoline - the 21st-century information superhighway has its limits. You can't buy your next fill-up on eBay. Priceline.com in 2000 did allow users to name their price for gas, but that service disappeared after a few months - one of many grand but unsustainable ideas in the early, exuberant days of the dot-com era.
Even if you could buy gasoline in bulk on the Internet, you'd have no place to put it, so the best the medium can offer is to help you shop a little more wisely at the pump.
And as the price of fuel rises near its all-time high, more people are checking out price sites such as gasbuddy.com, autos.msn.com or gasprices.mapquest.com.
The national average retail price for gas has risen 30 cents in the past month to $3.279 a gallon, passing the all-time high set last May, AAA reported last week.
Last year, the association had about 25 million visits to aaafuelgaugereport.com and about 5 million to aaa.com/fuelcostcalculator. That was double the traffic of a year earlier, according to AAA spokesman Geoff Sundstrom.
Oil Price Information Service, a Gaithersburg-based company, provides live gas price information to GPS sellers such as Garmin and Tomtom, whose higher-end models can inform drivers about the cheapest gasoline wherever they happen to be.
"There are a lot more people interested in what gas prices are doing and how to save as much money as possible," said Fred Rozell, retail pricing director of OPIS.
A "work-life balance" Web site called reallifesolutions.com recently offered 10 tips on how to conserve gasoline, including:
Purchase gasoline when it's coolest outside, such as in the early morning or at night, since gas becomes denser in lower temperatures and you'll get a little more for your money.
Religiously check your car's tire pressure each month (with a high-quality dial-type gauge, not the less reliable pencil-style gauges, it said), because fuel efficiency is reduced by 2 percent for every pound tires are underinflated.
Even on cold mornings, cars don't need to idle more than 30 seconds. Newer cars are designed to be driven almost immediately and letting your car idle longer is a waste of gas.
Don't use your trunk as idle storage space. Unnecessary weight reduces fuel efficiency by about 1 percent for every 100 pounds.
Not atypical for the Web, you're as likely to find arguments online that you stop whining about gas prices because (a) other countries have it worse or (b) the prices of plenty of other things are going up too.
A frugal-living blog called wisebread.com compared the price of a gallon of gasoline with a gallon of 40 other common household liquids. It concluded that even in expensive Northern California, gas was cheaper by the gallon than milk ($3.99 a gallon), Coke and Pepsi ($5.33, even though, as someone pointed out, no wars are influenced by a threat to the supply of Coca-Cola), Minute Maid Orange Juice ($6.99), Dawn Dish Detergent ($11.43), Windex ($17.29), Old Spice Body Wash ($41.17) and Krazy Glue ($2,322).
Some respondents pointed out that the comparison shouldn't be so startling: Air and water are cheaper than gasoline, despite being more necessary for survival. And gasoline doesn't require the packaging costs of the other products, although it's long been a heavily marketed commodity, more so than milk or Krazy Glue.
"When Exxon reports that it is earning 10 million dollars per hour, I have trouble with anyone trying to explain that we should feel like we're getting a bargain!" wrote one unconvinced reader.
Several sites can hone your understanding about gasoline policy and pricing, such as fueleconomy .gov, peakoil.com and bizmology, a blog site offered by Hoovers, a business information provider.
"If you are as surprised about this as President Bush was at a recent White House press conference, then let me enlighten you," energy writer Stuart Hampton offered on bizmology. "The growing demand for oil from the burgeoning economies of China and India is soaking up an only slowly growing global oil supply, and the limited refining operations in the US (where no oil refinery has been built in 30 years) is a major factor putting pressure on the price of gasoline.
"But in that news conference the CBS News Radio reporter suggested that the possible spike to $4 is also due to the reformulating of gasoline blends that occurs in the spring. Because of stricter requirements for summer blends of gasolines than for fuels sold in the winter season, there is a spike in prices associated with the higher refining costs that go with producing the summer blends. Taken together with the dollar's slide and rampant crude oil prices, $4-a-gallon gasoline is nearly here."
Intelligent discourse about gasoline you can find on the Web.
Cheaper gasoline, not really.
Andrew Ratner, a former technology reporter, is Today editor of The Sun.