Only an estimated 20% of business travelers and 12% of leisure passengers have used the touch-screen devices in the past year, according to new figures from Forrester Research.

"It's like the island of unloved toys," says Henry Harteveldt, a senior analyst for Forrester who has studied self-check-in trends.

Still, experts expect popularity among business passengers to double over the next year as the systems continue to catch on.

Airlines are investing heavily in self-check-in kiosks despite the industry's economic woes. The machines allow carriers to process more passengers in less time. They also hold out hope that fewer gate agents may be needed in the future — though no major airline says it has reduced customer service staff yet as a result of the technology.

Passengers can receive boarding passes and drop off their luggage usually in less than a couple minutes.

Kinetics, a major maker of the kiosks with 70% market share, says it has sold more than 2,000 machines. They are being installed in 120 airports nationwide, many of them in the past year alone.

Some airlines have offered inducements such as bonus frequent-flier miles to encourage first-timers.

"Airlines are rolling them out faster than customers are adopting them, but they are very effective devices," says airline analyst Sam Buttrick of UBS Warburg. "Some people get to the airport, look for the longest line and figure that's where they should be."

A regular user himself, Buttrick says he's never had to wait to use one.

Three out of four users are the classic early adopters — higher-income, technology-oriented people traveling on business and in a hurry, Forrester says.

American Airlines says its passengers successfully complete the transaction about 85% of the time. But travelers who are unable to get the kiosks to work the first time are hesitant to try them again.

"Most of the time, they don't work for me," says Doug McCausland, 31, a Chicago insurance agent who has tried kiosks.

Airlines are posting extra workers by the machines to try to shepherd travelers through the process. "If I saw a line, I would go over and invite people to come and use they machine. I was always successful," says Allison Hunt, who was a "Rapid Check-in Ambassador" when Southwest Airlines unveiled its first kiosks at Dallas' Love Field.

Experts say objections are melting away just as they did for automated teller machines. As more self-service check-in kiosks are installed and more passengers try them, they will become the norm.

"Anyone who can use one of these machines and doesn't is a blithering idiot. It can save you so much time," Harteveldt says.