At the New Flesh Workshop, a big, bright space on the barren outskirts of Queens, New York, everything is coated in a fine white plaster dust, and mannequin parts are strewn across the floor. It's here that Dr. Seth Adventure (real name: Seth Kane; also, not a doctor) fabricates tools for what he calls "human enhancement." There's a bulletproof leg in a protective case lying in a corner; molds of silicone ears with embedded hearing aids are piled on an oversize workbench; prototypes of an implantable electromagnetic "muscle" the size of a pencil eraser sit near the keyboard of his iMac. (The implant, he explains, attaches to tendons or bone and through a coil will contract and move soft tissue, allowing those who have lost the use of a limb to regain some mobility.)

At 28, Adventure looks every bit the part of a hipster tinkerer, sporting an anachronistic mustache, thick-rimmed glasses, and a pair of faded thrift-store jeans. Today he's eager to test out his latest invention: a flexible exoskeleton made from a carbon-fiber composite, which he created for rescue workers and has asked me to try on. "We don't have any cinder blocks here, so how about I hit you with this hammer?" he asks, waving a Craftsman. He winds up and delivers a two-handed wallop to my lumbar. He belts me 10 or 15 times. It doesn't not hurt, but I'm still standing, bones intact.

A former science instructor and circus performer who's a few credits shy of a bachelor's degree in biomedical engineering, Adventure is now a full-time biohacker, one in a growing movement of amateur scientists who, over the past decade, have been conducting ambitious, unregulated experiments in makeshift labs. (According to the Woodrow Wilson International Center for Scholars, the DIY-biology community grew more in the second half of 2013 than in any previous time.) Though biohackers vary greatly in their pursuits and personalities—they range from teenagers in after-school programs manipulating plant DNA to CEOs using smart drugs like nootropics to boost their God-given biology—the intent is the same: Embrace an open-source ethos (i.e., share findings and instructions online) to quicken the pace of scientific advancement. "Science used to be people doing crazy and dangerous shit to find knowledge," Adventure says. "But it became this massive, sterile industry. We do things our way."

Adventure believes that beneath the dust may be a fix to issues too narrow to draw the attention (and funding) of Big Medicine, like prosthetics for people with rare disabilities. And though some projects sound like props in a sci-fi film, it's hard to dismiss young people who think they know better: Consider 21-year-old Palmer Luckey, who built the prototype for a virtual-reality headset, Oculus Rift, in his parents' house, then sold it and his company to Facebook for $2 billion. "Every major industry that's been launched in the United States has been launched outside of an establishment," says Oliver Medvedik, Ph.D., a biomedical scientist and cofounder of GenSpace, a DIY-biology lab in Brooklyn. "The aerospace industry was started by two bike mechanics in a shop in Kitty Hawk, North Carolina—NASA didn't fund the Wright brothers. Jobs and Wozniak launched the PC revolution in a garage."

Much like Adventure, Amal Graafstra took things into his own hands, literally, when he had an idea for revolutionizing how we open doors. While working as an IT consultant in Seattle in the mid-aughts, Graafstra was locked out of his office regularly, and it got him thinking about the archaic nature of keys. His interest in transhumanism—the belief that man can evolve beyond his own physical and mental limitations—prompted him to investigate the radio frequency identification (RFID) chips that veterinarians implant in pets. "There's a difference between carrying a tool and integrating a tool into yourself," he explains. "It expands your expected set of capabilities." Graafstra programmed a chip and had his GP insert the glass-encased tag into the fleshy area between his right thumb and forefinger (the cylinder is slightly larger than a grain of rice). He installed an RFID reader on his office door and, just like that, no more keys. He added one to his car, his front door, and his office safe; he waves his hand in front of each to open it. "Biohacking is an iterative process," he says. In other words, each experiment moves the science forward.

Unlike in traditional research—with test subjects, waivers, and red tape—using oneself as a guinea pig is common in biohacking. A sect called grinders prides itself on it. One notable group, Grindhouse Wetware, gained national attention when one of its founders, Tim Cannon, implanted a biosensor in his arm. Built by engineers in his basement, the sensor, called Circadia, is the size of a soft pack of cigarettes. It transmits weeks of data on Cannon's temperature and pulse to his cell phone via Bluetooth. This procedure, performed by a body-modification artist (a pseudo–plastic surgeon who might carve elf ears or implant metal bolts in a client's neck) during a German biohacking conference, served as proof of concept: The technology of monitoring yourself from within is basic, but it can be done.

Considering the near-ubiquity of the quantified-self movement (obsessing over REM cycles and caloric intake has become de rigueur for type-A personalities), the implications for an implanted data-collection tool would seemingly have investors seeing dollar signs—one estimate predicts that wearable tech will be a $101.2 billion industry by 2018. This spring, Grindhouse started working to make Circadia smaller, with a better battery and fuller functionality, so that, as another of the group's cofounders, Lucas Dimoveo, puts it, "people feel it's acceptable to have one." But not everyone shares that goal. Dimoveo says there's a nonconformist streak among grinders, who see personal augmentation as a means of self-expression, not performance enhancement. In fact, there's often an overlap between grinders and body modifiers—the folks with synthetic horns and forked tongues.

Although that bizarre aesthetic could hinder biohacking's entry into the mainstream, the body-modification crowd may be essential to making these implants accessible. While Grindhouse members were developing Circadia, people in other hack labs were also experimenting on themselves. After receiving an e-mail from a young woman who landed in the hospital with sepsis from attempting to put a magnet in her hand, Graafstra launched Dangerous Things, a company that sells instructions and safety materials for RFID implants, and curated a network of body-modification artists to safely install the chips, since many doctors won't. "Maybe someday a major company will offer to mass-produce these things," Graafstra says. "Until then, [biohackers] are breaking ground, not just on the technology, but also the acceptability of it. We're letting people play around, get used to it. It has social value."

Still, the question remains whether a sparsely funded industry populated mostly with part-time enthusiasts can change the way we live. Money, lab space, and motivation are hard to come by. Tom Burkett, founder of the hack lab BUGSS (Baltimore Under Ground Science Space), says that biohackers frequently brainstorm far-fetched solutions to important problems but that technology and funds take time, and the lack of immediate feedback frustrates many. Adventure sees only possibilities. "You know what biohacking could lead to? Human photosynthesis," he says excitedly. "You'd get an inoculation. Instead of eating, you'd sit in the sun and have nourishment." His voice carries no hint of recognition that the idea is ridiculous. But then again, at one time, so was flying.

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