A little octane is being thrown into vacations at the Royal Kona Resort.

Guests vacationing at the hotel can get a $50 gasoline card under a promotion by the oceanfront property. The same goes for its sister property, the Royal Lahaina Resort at Ka'anapali. Other hotels here are offering variations of the free-gas theme.

Moreover, the gas giveaways aren't restricted to hotels. Businesses are climbing on the petroleum incentive bandwagon as prices at the pump jump.

"Gas is top of mind for everybody," said Shannon Scott, promotions director for KCCN FM 100, which also is getting into the gasoline-as-an-incentive game, starting tomorrow with its own promotion. It's giving away $100 of petrol from 76 stations over a three-week run.

"It's a hot topic with everybody."

Gasoline has replaced UH football tickets and road trip giveaways as the hottest incentive prize in Hawai'i, with companies ranging from automobile insurers to a Kaimuki parcel service to automobile dealers promising free fill-ups. The Sea Country housing development in Ma'ili last month advertised a $400 gas giveaway to people who stopped by and visited its model homes.

The special offers are cropping up at a time when gasoline prices are setting records and posing concerns for budget-conscious motorists. Last week, the statewide average price of a gallon of regular breached the $4.50 mark.

Hawai'i's gasoline is the second-most expensive in the country and has doubled in price over the past four years as crude oil costs spiked.

At the Shipping Shack on Wai'alae Avenue, owner William Donohoe is giving customers who spend $50 a certificate for $10 of gas. Those who spend $100 get one for $25 of free gas.

Donohoe said he pursued the idea of a gas giveaway after reading about businesses on the Mainland enacting the free promotions. He's hoping to drive up volume for his shipping business during what has been a slow time. If he reaches certain thresholds, he can get discounts with United Parcel Service or FedEx.

After discovering that gas cards would cost him at least $1.25 on top of their face value, he went to St. Louis Shell Service and worked out a deal where his certificates would be honored at the station. Donohoe said the offer helps the service station since its volume is down because of people cutting back on driving.

"I just want to get my volume up," said Donohoe, who has run the promotion for the past two weeks. He also gives the certificates out to people renting mail boxes at his store or those subscribing to the Mobi PCS mobile telephone service that he also sells.

Donohoe's offer is one of the more unusual ones since most of the deals being advertised are related in some way to automobiles or traveling.

Tanks of gasoline with the purchase of a car can easily be found at automobile dealerships around the state, such as one Servco offered in mid-July. People who purchased a Chevrolet Silverado could get a $2,000 gas card, while there was a $1,500 one offered for those buying a Malibu LS.

Perhaps one of the better-known promotions nationally is the $2.99 a gallon guarantee for three years on select Chrysler, Jeep and Dodge vehicles. Buyers receive a card guaranteeing the price for motorists who drive up to 12,000 miles a year.

Because of Hawai'i's high fuel prices, the program has some of the best cost-saving potential here. For example, if gas remains at $4.50 a gallon here for the next 36 months, a driver traveling 12,000 miles a year in one of the cars getting 24 miles a gallon would use 500 gallons of gas annually and save $1.51 on each gallon.

That works out to a savings of $755 annually, or $2,265 over a three-year period.

Depending on the manufacturer, though, there may be strings attached to getting the free offer.

A Mainland blogger complained about his experience at a dealership, writing that getting a $500 credit involved waiting weeks for his account to be activated after paying a $5 fee. He wrote that there were requirements on where he could buy gas, the mailing of receipts and vouchers and other actions that seemed designed to discourage use of the card.

Other offers are more straightforward, such as getting a $5 gas card for getting a quote from DTRIC Insurance, or an offer from Hertz that gave AAA members a free tank of gas when they rented a full-size car for three days.

Some businesses just deduct the so-called gas credit from what they charge you.

Garvin Goode, who runs a Hilo bed and breakfast with his wife, Laura, gives guests $25 toward their gasoline tab when they book two nights at his eight-acre estate overlooking Hilo Bay. Goode said guests taking him up on the offer get the money in the form of a credit on their bill.

Goode said he believes the discount offer has helped him attract business at a time when Hawai'i's tourism industry is scratching for every visitor it can get.

"Everybody is so price conscious these days," Goode said.

"Anything that helps someone's pocketbook should give you a leg up."