Want a stranger's half-eaten pizza? Need to rent a treehouse? Technology can help

New social media groups and smartphone apps are redefining how we barter, lend, buy and give in 2013

In traffic-insane San Francisco, where motorists fight through the nation’s third-worst gridlock and cope with parking hassles, Laurie Jo Miller Farr turned to the Web to alleviate some headaches for her — and for other drivers.

Through a local startup called ParkPlease, Farr earned $200 renting her home’s driveway in the city’s Inner Richmond neighborhood to “someone I never met and probably never will.” For about $18 to $90 a day — depending on car size, location and security needs — ParkPlease hooks up parking spot owners with drivers tired of the circling-for-a-spot aggravation.

“Better the $200 goes to private individuals than to the price-gouging tow companies that cities contract with to resolve parking problems in the traditional way,” Farr shared in a first-person account she wrote for Yahoo.

She used the service when 75,000 people descended on Golden Gate Park for the Outside Lands music festival and clogged nearby neighborhoods.

“I am happy to share,” Farr says, “since I don't have a car.”

She returned that car — her leased Volvo — to the dealership in favor of Zipcar, a car-sharing program found in many cities, and Lyft, a smartphone app that lets people avoid cabs and instead hitch rides with strangers.

Farr, 57, says she saves hundreds a month and her quality of life has improved: “Taxi service is notoriously poor in San Francisco, some hills are too steep for groceries, and buses cannot help with heavy lifting.”

Those services are just small examples of how technology in 2013 further helped Americans sell, barter, lend, rent, swap, share, recycle or just plain give stuff away. An added benefit: Social media and smartphone apps — that same ubiquitous tech we routinely pillory for pushing us further apart and damaging our relationships — are somewhat ironically helping us forge local communities again.

Here are more ways we’re sharing:

Tired of your wardrobe? Rehash Clothes helps you trade your threads. Sick of your city loft and looking for something more pastoral? Try GoSwap and permanently trade in your digs. Ordered too much Chinese takeout and feel guilty tossing it? Someone on LeftoverSwap might want it.

Travelers have especially benefited in the bartering economy. HomeExchange.com, around since 1992, says its nearly 50,000 members will have swapped more than 75,000 homes in 154 countries by the end of the year, with 16 percent growth in 2013.

HomeExchange CEO Ed Kushins says better technology draws more consumers to these models: “[Previously] it was almost impossible to find the people who either wanted or could provide the services or products that you wanted to barter, share, exchange or rent.”

Kushins, who founded the company in 1992, calls these economics “collaborative consumption,” or more simply: “You stay in my house. I stay in yours. No money changes hands.” HomeExchange allows travelers to temporarily trade the mundane — say, their suburban St. Louis home — for an exotic Costa Rican treehouse. But it’s more than a swapping exercise; it’s immersive community building.

“There can be hardly anything more personalized,” Kushins says. “You literally assume the home and the life of the people who you exchange with. You meet their neighbors, you often use their car, you use their refrigerator.”

Few reliable statistics indicate how much Americans trade, in aggregate, in their daily lives. But the International Reciprocal Trade Association, a nonprofit organization that promotes global bartering, says more than 400,000 of its members created $12 billion in bartering revenue in 2012.

Democratizing how we eat

The local food industry — and its growing, trading, marketing, selling and giving — is ripe for a technological boost.

Melanie DuPuis, a sociology professor at the University of California, Santa Cruz and an author who studies food and agriculture, says consumers do use technology to improve local food hubs, which connect farmers directly to consumers. And some tech startups are energizing person-to-person food distribution. But it’s not there yet.

“It’s a matter of coming up with ways that people can connect to each other to get local food distributed more efficiently,” DuPuis says. “The challenge that everybody sees now is that farmers markets are great. But they’re the world’s least sustainable in terms of transportation and farmers’ time. How do you go about making a local food system more efficient and still make it farmer-to-consumer?”

The market for local food transactions is growing. According to the USDA, farmers are increasingly connecting to cities and suburbs through food hubs. Ninety-one percent of food hubs are near cities, and that proximity helped drive $3.7 million in farmer-to-consumer sales over the last 12 months. The USDA says there are now more than 230 food hubs in the United States, a 65 percent increase since 2009.

DuPuis says food communities follow the meet-up model through which local residents pursue shared interests, and social media, in particular, plays a burgeoning role. But local food is still complex. She says, “I don’t think they haven’t quite figured out how to make that a user-friendly drop-in system.”

Smartphone apps like LeftoverSwap attempt to solve a small slice of that problem. The 4-month-old Seattle-based company encourages locals to swap or give away their leftover lasagna, extra egg salad and half-eaten hamburgers to neighbors — or, for those grossed-out by partially eaten meals, their unopened but unwanted canned goods and boxed meals.

“It’s Craigslist for leftovers,” co-founder Dan Newman says.

The app’s users post photos of food they don’t want and ask for takers. The idea germinated one night in 2010 when Newman and co-founder Bryan Summersett stared down their half-eaten pizza and wondered how they could get someone in their area to finish it. Their first victory: A Manhattan resident used their app to give away a bag of Popchips in 15 minutes.

“It’s not for everyone. Food is a very personal thing,” Newman says. “There are different levels of comfort toward different foods.”

Eliminating food waste — “and all the resources we put into food, making food, distributing food, preparing food and then taking that wasted food back to a landfill,” Newman says — and building community are central to their plan. In a few months, they’ve convinced 7,000 users to give it a shot.

“We live in these apartment buildings [where you don’t] know a neighbor. That’s insane to me,” Newman says. “These sharing apps let us get back to borrowing a cup of sugar from a neighbor.”

Some barter through social media on a small scale.

Janoa Taylor lacks space to grow large plants in her Chicago apartment, so she hopped on Facebook to locate nearby similar-minded folks looking to barter vegetables. On her window sill, she raises fast-growing herbs like alfalfa sprouts, cilantro and oregano and swaps them for tomatoes, bell peppers, squash and cucumbers — food she can’t grow at home. Even on such a small scale, she estimates it saves her about $25 in monthly grocery bills.

In suburban Sacramento, Calif., after Nancy Tracy noticed “30 pounds of fat that had mysteriously attached themselves” to her, she joined a Facebook group called “Medifast Buy, Sell, Trade,” a 400-person community that offers diet meals at below-retail costs, and swaps weight-loss counseling and other related services — essentially among strangers.

Tracy, 55, estimates she saved about $63 monthly since joining the group. She also bartered advice from a health coach in the group.

“When I first joined the group I felt like an interloper, but after commenting on a few posts, I was accepted as part of the club. Occasionally we go off topic and fantasize about what kind of new meals we'd like to see (curry and popcorn top the list) and how we're coping with holiday temptations,” Tracy writes in a first-person account she shared with Yahoo. “We have become a support group for each other.”

And she’s lost 22 pounds.

Redefining how we give

At one end of the giving and bartering spectrum sits the Buy Nothing Project, a 5-month-old “gift economy” with more than 10,000 members across 57 groups in 13 states. Started by Liesl Clark and Rebecca Rockefeller in Bainbridge Island, Wash., the project encourages its members to re-examine the mounds of stuff in their lives and consider giving it away. Neither trading nor selling is allowed.

“It’s collaborative sharing,” Clark says. “And the technology is enabling us to do it.” Through the project’s many Facebook groups, members can see what’s offered through photos and comments. They discuss offers, establish rules and crowdsource the best candidates to receive gifts. “We can crowdsource behavior. There is total transparency.”

In the Buy Nothing Bainbridge group this week, members’ gifts ran the gamut, for instance: a 22-inch Pluto pillow pet, doll house furniture kits and a half-case of red delicious apples. Givers get creative when choosing a recipient: Some ask for haikus, or use random-number generators, or prompt askers to share anecdotes about positive acts they performed.

“Initially people might think, ‘Oh, it’s about free stuff!’ But in the end, what everyone is finding is that it’s so much more about community. People are starting to meet each other, and they’re walking outside of their homes. And they’re truly connecting,” Clark says.

Clark offers a couple examples: A foster child, after receiving clothes and other essentials from a family in the group, offered her stuffed Daisy Duck toy — one of her few possessions — in gratitude.

“This is a priceless lesson on giving freely with no expectations,” Jill Hendren, the mother of the children who gave their clothes, wrote about the experience.

“We’re redefining what a gift is,” Clark says.