Gerd Kortuem likes a catchy tune, but considers himself clueless when it comes to seeking out new music. However, instead of asking his friends what they are listening to, his iPAQ PocketPC does it for him.

Whenever Kortuem sits down with another participant in his ongoing experiments at the University of Oregon’s Wearable Computing Lab, his iPAQ establishes a Wi-Fi link with his colleague’s device. It checks the user’s identity, and if the person is someone whose taste Kortuem has noted as trustworthy, it downloads an MP3 playlist ranked according to frequency of plays. Later, Kortuem culls through the lists he has harvested. “I rediscovered David Bowie and the Talking Heads,” says the 38-year-old assistant professor, who recently moved to Lancaster University in England. “I knew I liked them, but I had forgotten all about them.”

The iPAQ doesn’t quite qualify as a wearable but it’s a step toward Kortuem’s vision. Wireless wearables, he says, can link like-minded strangers in a new kind of social organization he calls an “ad hoc community.”

As he sees it, the crowds who surround us every day constitute a huge waste of social capital. If you live in a city for instance, there are many who pass within a few yards of you each day who could give you a ride home, buy an item you’re trying to sell, or consider you as dating material. Dynamic networking makes it possible to tap those resources through a momentary alliance among transient interest groups, “like people working in a given neighborhood, staying overnight in a certain district, or taking the 10:15 flight to Chicago,” Kortuem explains.

In a world of wireless wearables, computers embedded in clothing could form networks on the fly, prompting software agents to carry out mutually beneficial transactions. A group waiting to buy movie tickets might use an ad hoc network to auction off favorable places in line. Thousands of people in Times Square could pool computing power and sell it by the teraflop-second to nearby office buildings.

Kortuem is part of a growing freemasonry of researchers looking beyond the individual personal-area network to the frontier of social computing. Research into wearables, which began in the 1970s, is hot at a handful of universities (MIT, Georgia Tech, and the University of Toronto) and commercial labs (Sony, Microsoft, IBM, Hewlett Packard, Ericsson, and Nokia). As researchers cleared the early technical hurdles, networked groups of wearable users could exchange experiences and knowledge, share resources, collaborate, play games.

By and large, these efforts have involved participants who know one another, but Kortuem’s hypothetical communities could be made up of strangers. “I want to make it possible for people who don’t already know each other to interact productively,” he says. “The biggest effect of mobile wireless computing devices will become visible only after large numbers of people start using the technology to engage each other.”

While other early pioneers of wearable computing, such as Thad Starner, director of the Contextual Computing Group at Georgia Institute of Technology, and Steve Mann (see Cyborg Seeks Community, TR, May/June 1999), focus on developing systems to create communities, Kortuem attempts to show how communities of computer-wearing users might cooperate if these systems enabled them to find their own connections.

Kortuem, who came to the University of Oregon from Germany in 1993 on a Fulbright grant, witnessed an early example of this sort of spontaneous interaction while studying for his master’s degree in computer science. During the summer, he took an internship at Apple, where he worked on software for the Newton PDA, an early handheld with an infrared communications link. He became fascinated by the way Newton users beamed business cards from one unit to another. Familiar with the emerging power of desktop-bound Internet communications, he realized that networks of wearable computer users would hold the potential for an entirely different medium. As much as the PC was changing the world, its impact would be severely limited by its stationary character. Portable devices would be networked wirelessly within a decade, and the killer apps would be social.

The University of Oregon was the right place to pursue such ideas. The same year Kortuem arrived, Zary Segall, formerly of Carnegie Mellon University, one of the birthplaces of wearable computer design, cofounded the Wearable Computing Lab with University of Oregon Computer Science Professor Steve Fickas.

Kortuem and Jay Schneider, another graduate student, began assembling hardware/software packages capable of automatic wireless interactions. In 1999 the team completed its first ad hoc community application called Walid, a program that negotiates chore sharing among parties with complementary tasks on their to-do lists. The software agents representing each party might determine, for instance, that one person could pick up some blank CDs at the store if the other would return a book to the library. The playlist-sharing application, known as Pirat, came next, followed by mBazaar, which mediates swaps of CDs, books, bikes, furniture, and electronics.

It soon became apparent that ad hoc community applications relied on a common set of functions, having to do mostly with detecting nearby parties, querying and comparing information, and keeping track of contacts. Kortuem realized that putting these functions in a common code library would speed up development. Completed in mid-2001, the Proem peer-to-peer platform consists of 135 Java commands optimized for spontaneous social organization. “You can have a message that’s sitting in your buffer delivered whenever you meet someone,” Kortuem explains. “You can say, ‘This message is only for people nearby,’ or you can send it to nearby devices and have them route the message further.”

The tricky issue is trust: You don’t want to link up with the wrong kind of crowd or surrender your privacy to the nearest vendor without a fight–or at least an auction. The Proem architecture allows peers to form groups of mutually trusting devices, according to a specification published by the Oregon team in 2000 for “Disseminating Trust Information in Wearable Communities.” Each time agents exchange information about a transaction, they can also exchange data about past transactions, like a decentralized version of the reputation system on eBay.

As he gears up for his one-year residency at Lancaster University, Kortuem’s most pressing challenge is lack of hardware capable of running the kinds of programs he has in mind. “We’re in dire need of a next-generation wireless device specifically designed for ad-hoc wireless connectivity,” he says. In addition to iPAQs, Kortuem’s arsenal includes Cybiko wireless PDAs (“not powerful enough for our applications”), a Via belt-worn computer, and a jerry-built machine whose parts are distributed among the pockets of a fishing vest.

Kortuem hopes to devise better hardware at Lancaster, but his priority is expanding his trials to encompass larger groups. “At the University of Oregon, we proved that the technology works on a small scale,” he says. “At Lancaster, I’m getting a larger community up and running and concentrating more on how the community works from a social point of view.”

The Oregon and Lancaster experiments are a first step, but Kortuem sees significant large-scale applications as the technology matures. He imagines “helper communities” whose members pledge to assist one another, along with “bargain-hunter communities, marketplace communities, job-market communities, knowledge communities, and political communities.”

For the time being, small colonies of radio-linked cyborgs will be confined to campuses and commercial laboratories. Within the next decade, though, networked social encounters may well escape the desktop, perhaps riding on clothing–our most mobile and intimate technology. What then? Could a Napster-like contagion break out among riders on a subway car? Could an ad hoc recommendation system connect you to strangers who share your commercial, intellectual, or sexual predilections?

Before the Net, community was mediated by physical proximity. Online communication reinvented the concept as a social sphere you could log into from your desktop computer. If Kortuem is right, one day the most important factor in social success won’t be who you know, but who your wearable knows.