When the Department of Homeland Security announced strict new policies for air travel in the wake of British terrorism arrests in August, two sounds rippled across the country. One was a collective moan of inconvenienced frequent fliers. The other: “ka-ching.”

The Transportation Security Administration's (TSA) new rule forbidding airline passengers to carry on liquids and/or gels has turned into an added headache for some and a business opportunity for others. The TSA targeted liquid and gel personal items specifically because the alleged plotters in the Aug. 10 British bust were accused of planning to use the same type of items to blow up trans-Atlantic airliners in mid-flight.

On the must-leave-behind list: aerosol bottles and cans, creams, suntan lotions, moisturizers, more than 4 ounces of eyedrops or saline solution, gel-based deodorants, hair gels and sprays, lip gloss and lip gels, liquid foundations, perfume, liquid mascara, nail polish, makeup remover and facial cleansers, mouthwash, toothpaste, shampoo and beverages. Baby formula and certain liquid medications are still allowed on the planes.

Air travelers, already burdened with long lines at security checkpoints and requirements such as taking off shoes and handing over Swiss Army knives, were less than pleased.

“I got cleaned out in Long Beach, Calif., on my way to Oakland last Wednesday after walking through at JFK on the way out to Long Beach. Mouthwash, toothpaste, deodorant, cologne, Icy Hot, the lot,” said New York public-relations specialist Christian Averill.

John Chiang, 23, who was returning to school in New York after visiting family in Alabama, took extra precautions to follow the new regulations, but was still delayed.

“I took the advice from TV news and arrived at the airport two hours early,” Chiang said. “Security was extra tight, and it took extra time for the security guards to thoroughly search for 'liquids' that individuals might be carrying. People were forced to throw away their makeup and perfumes. Security guards took extra time searching my bag for a bottle of Wite-Out that I forgot I had.”

Some businesses are making changes to accommodate affected patrons.

Hotels stepped up to the plate. Marriott International currently offers guests in all of its 2,002 North American locations a free “Customer Care Passenger Kit,” including banned toiletries like shaving cream, mouthwash and deodorant. Gift shops inside the chain’s hotels have been ordered to offer retail-sized personal products alongside postcards and novelty hats.

“We feel it would be a great amenity to them at this time,” Marriott spokeswoman Dasha Ross said. “There's been an increase in requests for the items they aren't able to take with them; that's what we've seen across the board.”

Other hoteliers have had similar ideas. The Hyatt Key West Resort & Marina and Hyatt Regency Aruba Resort & Casino both have their gift shops stocking up on liquid- and gel-based products and staying open later. Complimentary items include shaving cream, toothpaste, razors, deodorant, moisturizer and other such items.

Rental-car company Avis — in partnership with Procter & Gamble — also switched gears to fulfill air travelers' needs. Starting in mid- to late-August, those in Avis' preferred-customers program in 25 airports around the country opened their rental-car doors to find a “Smile Pack” — filled with toothpaste, floss and mouthwash.

“We're happy that something so small could make people so happy,” Avis spokeswoman Susan McGowan said. “The feedback's been amazing. It's quite popular.”

Unfortunately for air travelers, it's also temporary. Avis and Procter & Gamble made up only 25,000 Smile Packs, and there are no plans to continue the program once the supplies run out, McGowan said.

Some marketing experts see the new carry-on restrictions as a business opportunity. And they say businesses should not miss the boat.

“The opportunities are enormous, and this event can single-handedly determine the success and failure of future products,” said marketing expert Liz Goodgold. “It's an opportunity for new packages, new sizes and new formulations. Marketers can seize this opportunity, but I haven't seen it yet.”

A spokeswoman for Johnson & Johnson's personal-products division, for example, could think offhand of no new marketing schemes or products to address the new TSA regulations — a golden opportunity gone to waste, Goodgold said.

“I can't wait to see a little kiosk at the airport that sells little Ziploc baggies. Johnson & Johnson could set up its own kiosks. Samsonite could create special soft non-leaking packaging for all the new materials that will go into checked baggage,” Goodgold said. “If you're Postal Annex, or UPS, why don't you set up a kiosk right there so you don't have to throw away $700 of cosmetics and can ship it home? I haven't seen anyone step up to the plate.”

Goodgold also said the new regulations could spur product lines.

“We're used to having instant products, but the wave of the future will be going back to the powders -- cake mascara, cake foundation, powdered toothpaste -- where you add water when you get to your destination,” she said.

“One of the hottest products right now is lip gloss; female customers may permanently switch to lipstick, which you can bring on board, and let go of lip gloss," she continued. "Think about the switch in products — if you're the manufacturer of Secret, you may see a huge merge from Secret liquid roll-ups to Secret stick.”

Johnson & Johnson still stands to benefit from the new world of air travel. It's been planning to roll out a flavored, chewable version of Tylenol in the next four to six weeks, which will come as a relief to headache-prone travelers who can no longer carry on bottles of water.

Some consumers have decided to try to avoid the TSA regulations altogether. Private-jet companies like Talon Air and Eos Airlines have been touting their services as safer and more convenient than the big airlines, and some are seeing results from frustrated fliers.

“Our phones have been ringing off the hook with inquiries from commercial consumers looking to switch to private air travel,” Talon Air CEO Adam Katz said in a press release. “More people are able to justify the cost of flying on a private jet because of the ease, convenience and safety of flying on a private plane.”

In the end, some frequent travelers say there is one thing Americans should stock up on when heading to the airport these days: patience.

“Truth be told, while it took a few extra minutes to get through security, I really didn’t mind,” Averill said. “I travel constantly and I’ve been pulled over for extra screening about four times in the past year … I can’t stand hearing people whine about extra screening. We may not have the right answer all the time, but this is not a game, you know?”