This week saw the largest known congregation of Google Glass users, those early adopters and chic geeks who have signed up to be the lab rats in a crowd-sourced experiment that will determine the shape and direction of the next big era of personal computing: wearable technology.
Affectionately referred to as "Glass-holes", they converged on the Moscone Centre in downtown San Francisco, where Google was holding its annual developer conference.
The object of their interest is a titanium-framed device that you wear across the face - spectacle frames without the conventional lens. Over the right eye there is a cube of glass that acts as a screen, and on the right arm there is a thicker mass of hardened plastic containing almost all the components you would find inside a smartphone. With this, the wearer can do almost everything that a smartphone can do, largely hands-free. A combination of voice recognition, head movements and finger strokes will allow the user to handle emails, read news headlines, get directions, make and receive phone calls and take and share photos and videos.
And, as this is just the prototype, there are bound to be more features when the device hits the mass market, probably later next year, along with smart watches, smart pendants and personal activity trackers.
Wearable technology has been made possible by recent advances in miniaturisation of electronics, longer battery life, and voice and gesture-recognition technology.
"We're at this moment where it's possible to imagine technologies on our bodies as extending us in ways that isn't just about physicality but also our sociality and our cognitive capacity," said Genevieve Bell, chip-maker Intel's resident, Australian-born anthropologist. "And it's no surprise that we're thinking about that because we're coming off the back of 10 years of mobile phone use," which she argues is just another type of wearable technology.
Many of the Glass wearers at the Google event were software developers who paid $US1500 for the privilege of being first. They are driven by a mixture of curiosity and the challenge of coming up with the killer app - the program or service that becomes the must-have utility. Google has also signed up another 8000 testers - ranging from celebrities and school teachers to a zookeeper who looks after the penguins at the San Francisco Zoo - who were selected after entering a competition to join the Glass pioneers. Their task is not only to come up with new ways to use the device but help establish a set of conventions for use which, by the time Google Glass is launched commercially, will soften the impact of what is shaping up to be a confronting new technology.
John Scheible, a 22-year-old computer science student from the University of Michigan, is one of the developers who signed up as a Google pioneer. Although he had only been in possession of his unit for 24 hours before we met, he had already given it the "really cool" tick of approval.
"I was interested in the new form factor and how people would interact with that," he said.
He is also acutely aware of the controversy swirling around the privacy implications of this type of technology, but dismisses it as a concern that will pass with time. "I think people are overblowing this a little. There are far sneakier ways to bring a camera if you want to be a creepy person, which is wrong and weird, but at least with Google Glass people know it has a camera."
People taking clandestine photos or video of other people is what has come to be known as sousveillance - a term coined by Canadian academic Steve Mann, who began experimenting with wearable cameras in the 1980s. Sousveillance ("sous" is French for "under") is the opposite of surveillance, the top-down and often recorded observation associated with governments or law-enforcement agencies.
Sousveillance evokes visions of being filmed by a neighbour through the fence or a voyeur aiming his camera at bodies on a beach. But it was also people-powered video footage that helped inspire the Arab Spring uprisings of 2010-11 and expose acts of police violence such as the Rodney King police bashing in 1991.
Australia's Federal Privacy Commission is one of several government and non-government entities to voice their concerns and ask Google for more details about how this new technology will work. And a grassroots organisation calling itself Stop the Cyborgs has also been rallying the doubters and sceptics and offering free download "Ban Google Glass" signs.
But while Google has become the public face of wearable technology, it is not the only company with devices that, as a by-product of their features, are able to push the privacy bar down even lower. Last month, the Australian branch of the discount supermarket chain Aldi, was selling a $29.99 pen equipped with a high-fidelity microphone and camera able to take snaps and shoot several hours of high-definition video through a lens sitting above the clip.
Or take the case of a Swedish start-up called Memoto, which raised more than $US500,000 through the Kickstarter crowd-funding community to build a tiny wearable "lifelogging" camera. It hangs around the user's neck, snaps a photo every 30 seconds and costs $US279.
And Google is not the only player in the smart glass space. Sports glass maker Oakley already has a $600 pair of ski goggles on the market with some of the same features found in Google Glass.
Chinese web services company Baidu is also working on its own version. Apple and Microsoft have lodged patents for similar developments, while smaller firms with names such as Vuzix, TTP and Explore Engage all have a smart-glass concept in the works.
The push to extend personal technology - to have it not just with us but on us, persistently connected and augmenting and assisting our day-to-day activities - is already an unstoppable reality. "Until you get to enough in the marketplace where it starts to be a reality, I don't think we can say whether it's going to be good or bad," said Intel's Dr Bell . "It's certainly going to be fascinating. Can I think of a more interesting time to be in? No."