SNOWMASS VILLAGE, Colo. — The first time Kate Duncan rushed down a mountain on an Airboard, she liked it so much she bought her own board the next day.

This past Christmas vacation, she and her sisters got Mom to try it, too. One "Oh, god" and an expletive later, Eliza Duncan, 51, slid headfirst on her 4-foot-long, 9-inch-thick air cushion into a powdery snowdrift as her family cheered her on.

"A lot of my friends wouldn't do it," she said afterward on a clear, sunny day on gentle slopes on a public trail, not far from the Snowmass ski resort near Aspen. "I thought it was fun. I just didn't like losing control."

From tubing to Airboards to snow bikes, mountain resorts and guides are looking for new ways to get people outdoors and entertained. Reviews are mixed on whether the Airboard can bolster ski visits the way snowboarding has, but supporters talk it up as a niche snow sport that doesn't stress the knees.

Some say riding an Airboard is ultimate sledding. People who ride the 6-pound Swiss invention slide down snowy mountain slopes face first on polyurethane air cushions that look like blowup rafts with handles and a ridged bottom. Riders have been known to reach speeds of more than 80 mph.

"I call it the endorphin adrenaline cocktail," said Sun Dog Athletics owner Erik Skarvan, the only guide in Colorado to offer Airboarding.

Airboards got their start in Europe, where engineer Joe Steiner of Zug, Switzerland, spent 10 years perfecting their design. So far a handful of U.S. resorts allow them.

Hoodoo Ski Area in Oregon started allowing snow bodyboards three seasons ago as something new. Of the 869 season passes the ski area had sold by mid-December, two were for people who only do snow bodyboarding, general manager Matthew McFarland said.

"The reality is, I think Airboarding is going to be a small niche market. It's never going to be like snowboarding," said McFarland, citing complaints from skiers and snowboarders who are reluctant to share the mountain or who think that it's a kids' sport.

Still, it's a fun pastime for families with one person who doesn't ski or snowboard, or for people with weak knees, he said. In Aspen, more than half of winter visitors don't ski or ride, making Airboards a more inclusive activity, Skarvan said.

"If we get 5 percent of our business from it, that could be the difference between bankruptcy and having a good thriving business," McFarland said.

"It's like snowboarding; 20 years ago, everybody thought snowboarders were the devil. Now everybody's saying hallelujah for snowboarding or we'd be out of business."

No resorts in Colorado or Utah allow Airboards, although Keystone in Colorado tried it for a season. Tubing, ice skating, sledding and snow bikes have been more popular, representatives for Keystone and the trade group Ski Utah said.

Interest is growing though.

Emo Gear, the only licensed distributor of the Airboard in North America, started with five U.S. retailers in its first season in 2003. This year it has 90 in the U.S. and Canada, and President Ann-Elise Emerson says this is the first profitable year for the Berkeley, Calif.-based company as Airboards earn their own competitions.

Canaan Valley Resort in West Virginia began offering 18 rental Airboards this season and has sold out a couple of days, spokesman Bryan Brown said.

"We hope that by offering guests one more winter activity that they'll be more inclined to come to Canaan Valley," he said.

"It's new, exciting, anybody from 6 to 66 can do it. Unlike skiing or snowboarding, the learning curve is not as steep," Brown said.

Kids models run $149, with the Airboard Classic running at $269.

Kate Duncan, 25, has videotape of herself doing jumps her first time on an Airboard.

This past December, Kate Duncan, her 16-year-old sister, Lillian, their parents and 12-year-old cousin, Garrett Marsh, slung black bags carrying Airboards on their backs and snowshoed up a public trail with Skarvan as their guide.

They pumped up their Airboards within minutes, donned helmets and got pointers from Skarvan to lean their bodies in the direction they wanted to turn and to turn perpendicular to the slope to stop.

Their dad, Johnny, turned with ease on a groomed slope and even experimented with sitting upright and cross-legged on an Airboard.

"It's a rush. It's not something you get from skiing," Kate Duncan said.

Eliza Duncan, left, her nephew Garrett Marsh, 12, center, and daughter Kate, 25, pump up their Airboards at a public trail near Snowmass Village, Colo., watched by instructor Erik Skarvan. Tubing, Airboards and snow bikes offer fun, alternative ways to enjoy ski resorts.