AirAsia X passengers who want a coach row to themselves make the request through Optiontown.com. If the traveler can be accommodated, he or she is notified four to 72 hours before departure.

Imagine: You've boarded your flight and are comfortable in your seat when you get a good look at, or whiff of, your seatmate coming down the aisle toward you, and you wish you could have simply reserved the entire row to yourself. Sound familiar?

By then, of course, it’s too late to buy an extra seat or, on today’s increasingly full flights, move to another row. Buying an extra seat ahead of time is an option, but the hefty cost usually convinces travelers to take their chances.

Now some airlines are giving passengers another, less expensive, option.  

Empty Seat Option, offered on AirAsia X — the long-haul, low-fare affiliate of Malaysia’ AirAsia — allows passengers  to pay a fee and request that the seat(s) next to them remain empty.

It’s not a sure thing though.

Passengers make an empty seat request online at the Optiontown, a revenue-management site, and pay both a small sign-up fee (about $1) and an Empty Seat Price that varies by flight time and destination but can be as low as $6. If empty seats are indeed available, a passenger gets a confirmation message four to 72 hours before his or her flight. If no seats are available, the empty seat price — but not the sign-up fee — is refunded a few days after the flight departs.

“We offer them the option to purchase only what is required depending on individual needs rather than bundling the cost to our fare offerings,” Azran Osman-Rani, chief executive of AirAsia X, said in a statement. He added that so far feedback about the empty seat option — and a similar upgrade program — has been positive and that other flexible options would likely be added in the near future.

“It’s about providing passengers with choice,” said Raymond Kollau, founder of airlinetrends.com, an industry and consumer research agency. “Whereas KLM's social seating tool allows passengers in the mood for a chat to choose their seatmate, AirAsia X gives those passengers who like to have the row to their own an option to purchase it. It's just a matter of preference.”

A few other airlines offer a similar product. At check-in, Air New Zealand’s Twin Seat option gives passengers the chance to buy the seat next to them for a significantly reduced price. Spain’s Vueling offers a second-seat option, called Duo, as well.

“The option provides peace of mind to passengers who [don’t have to] bet on the seat shuffle that takes place after the aircraft has lifted off,” said Kollau.

Optiontown also offers an Upgrade Travel Option on 10 airlines, including AirAsia X, Aeromexico, SAS, Air India and others.

Shashank Nigam, CEO of SimpliFlying, a company specializing in airline branding and customer engagement, said it's a positive program. “It’s a great way to up-sell distressed inventory and also give customers a sense of what the premium product is like.” 

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Find more by Harriet Baskas on StuckatTheAirport.com and follow her on Twitter.

If you’re staying at a hotel or resort in the coming months, Bjorn Hanson has a little advice:

“Before you buy, use or do anything, ask if there’s a fee or charge involved,” said Hanson, who studies the lodging industry as dean of the Tisch Center for Hospitality, Tourism and Sports Management at New York University.

Why? Because according to Hanson’s research, U.S. hotels will take in an estimated $1.8 billion in add-on fees and surcharges this year. That’s a small (6 percent) increase from last year — due mostly to increases in occupancy, he says — but up a whopping 50 percent from the $1.2 billion they collected in 2000.

“They’ve become institutionalized as a revenue source for many hotels,” Hanson told msnbc.com. “They’re becoming more widely practiced and more guests are being surprised by them.”

Among those surprises:

• Baggage-holding fees: Checking out at noon but not flying home until 6 p.m.? While some hotels will still store your luggage for free, more are charging for the service. “They’re charging $1 to $3.50 per bag,” said Hanson. “That’s in addition to the expectation of a gratuity.”
• Minibar-restocking fees: According to Hanson, more hotels are charging a fee of $2.95 to $9.95 to restock minibars if even a single item has been removed. If you can’t resist the urge, “maybe you should buy more items to amortize the expense,” he said.
• Resort fees: These fees, which typically cover bottled water, use of the in-room safe, access to the fitness center, etc., can run between $8 and $40 per day. Worse yet, they’re generally mandatory, which means you’re charged whether you use the amenities and services or not.

“People hate resort fees more than anything,” said Anthony Curtis, who monitors the Las Vegas lodging scene as president of LasVegasAdvisor.com, an online newsletter. “We try to make the point that they can be reasonable if it’s something most people would use anyway, like Internet access, but people just don’t buy it.

“Our readers tell us it feels like a bait and switch,” said Curtis. “They’d rather see a higher rate that’s all-inclusive.”

Alas, the evidence suggests that travelers are more likely to see those higher rates but no decreases in add-on fees and charges.

“As hotel occupancy recovers, it will provide a sense of confidence on the part of hotel executives to implement more fees and increase the dollar amount of existing fees,” said Hanson. “Larger increases are ahead.”

More stories you might like:

• Slow economy benefits travelers who need a place to stay
• Need a room right now? Go mobile
• Expect fewer travelers, crowded planes this Thanksgiving
• NYT: Mobile boarding passes gain traction

Rob Lovitt is a longtime travel writer who still believes the journey is as important as the destination. Follow him at Twitter.