WHEN Southern Cross University PhD student Ivan Casselman discovered a hook on his tent was broken the night before a camping trip, he wasn't concerned.
He simply downloaded his preferred hook design from a free site and sent the virtual blueprint to his 3D printer, which, as he slept, squeezed out one layer of heated corn-derived plastic at a time to manufacture the perfect tent hook.
Dubbed the biggest thing since the home computer, 3D printing allows users to manufacture any real object from a variety of materials, many of which are made from cheap, renewable resources.
While most printed objects are made in homes and offices using LEGO-like thermoplastics, scientists from Cornell University last month showed it is possible to create an actual ear using a 3D printer and injections of living cells. This finding was a huge leap towards medicine's holy grail of tissue regeneration, previously the sci-fi fantasy of Arnold Schwarzenegger Terminator films.
If the price of 3D printers continues to drop, it's likely that very soon custom mini-factories will be commonplace in every home and, more importantly, in every isolated rural hospital and under-resourced classroom.
While Ivan and other early adopters all over the world have been manufacturing one-off hooks, customised iPhone cases and other innocuous trinkets for a couple of years without too much media attention, it's taken a group of gun-happy DIYers to captivate our attention and illuminate the technology's implications.
An online group called Defense Distributed has collaboratively designed Wiki Weapon, a gun made up of 3D printed parts, designed to be downloaded freely online. While early testing has shown the printed gun to be a great big fizzer - it failed after just six shots - the intent of the project has sparked real concerns.
In the US it is legal to create your own firearms but not to distribute them. However in the case of printed guns, where 3D patterns are shared over the internet but manufactured at home, the Wiki Weapon represents a legal minefield.
Like most home 3D tinkerers, however, Ivan downplays the failed gun experiments, staying calm and carrying on printing.
"For me, 3D printing represents a shift from a physical to an information-based economy. It's the information that people want to pay for and that has huge environmental ramifications.
"Objects don't have to come to us mass-produced in big, dirty shipping containers from China," he says.
Ivan observes that the printed objects of early adopters are manufactured with a customised approach, which imbues objects with more meaning and are therefore less disposable.
An iPhone case can be easily printed, for example, with a person's name or custom design. Designs are tweaked and shared openly on the internet and this collaboration makes for constantly evolving designs.
But the biggest benefit of the technology - and the reason early adopters are happy to pay more than $2500 for a machine that essentially produces small plastic toys - is for disadvantaged communities when prices fall.
If demand continues to rise in the Western world, 3D printers will be able to be produced cheaply enough to be distributed to isolated places where the supply chain of life-saving equipment is challenged.
Already, young university students have designed simple plastic water purification systems that can be manufactured anywhere for next to nothing.
"3D printing has huge potential in developing areas. Imagine bringing these inexpensive machines, powered by solar panels, into an isolated rural environment," Ivan says.
Customised prosthetic limbs and medical supplies, for example, could potentially be available to anyone, anywhere.
This may be a technology that can put DIY guns into the hands of anyone with an internet connection, but at the pointy end of 3D printing, scientists are exploring the technology's use for tissue regeneration and prosthetics.
So while the technology has opened a legal and ethical Pandora's box that needs to be addressed, the fact is that 3D printing doesn't kill people.
Idiots with DIY plastic guns could.
And if research continues, 3D printing might actually be able to repair any harm done by the idiots.
On the market
The MakerBot Replicator: $2100
RepRapPro (needs assembling): $599
Ultimaker: $2,200 (assembled) or $1200 as a kit
Printrbot Jnr: Under $400 unassembled