Everyone seems to have a different idea of what "hacking" means, but they can all agree that it has something to do with the laser in the bathroom.

What really pleases the members of the Toronto Hacklab isn't the fact that there's a laser in the bathroom (though, without a doubt, this pleases everyone immensely), nor the fact that the laser actually shoots things, carving up a sheets of plastic and sending the occasional piece of paper up in flames. No: the geeks like it so much because they made it themselves.

At least, they fixed it themselves. About the size of a large photocopier, the laser was salvaged with its electronics broken. Hacklab members ripped out its circuitry then installed a homemade circuit board and new controls and put it on the bathtub so they could vent the smoke out the bathroom window. Then they programmed it to play, unbelievably, a pitch-perfect rendition of the theme from 'Super Mario Brothers' with the whine generated by its aiming motors. This caught the attention of Cory Doctorow, world-famous technology blogger, who posted it on BoingBoing and soon it was a minor YouTube sensation.

This is what happens when the nerds run the school. Tucked into a cozy studio apartment above Graffiti's bar in Kensington, the Toronto Hacklab is part workshop, part tree house, and part revolutionary lair. It's what's called a "Hackerspace," and it's part of an innovative movement that's spreading across urban centres: real-world digs where members can break things, fix things, and most of all, make things.

"Everything you need to make your own stuff has become a lot cheaper," says Paul Wouters, one of lab's founders, who has just delivered a flaming-bathroom-laser demonstration. "You can build things -- cool things -- and it's affordable. Anyone with a regular job can buy a 3D printer, or buy electronics to drive a large LED board, or build a shoe with electronics."

Wouters gestures across the workbench he's sitting at. Opposite, a young redhead is, indeed, trying to wedge a circuitboard into a running shoe. The lab is open 24/7 for members who pay their $50 a month, which gets them workspace, tools, diagnostic electronics, Internet access, and the expertise of knowledgeable peers. But on Tuesdays they throw the doors open to the public, and on this particular Tuesday, the place is humming.

Tube-socked visitors -- mostly men, mostly young -- have plunked themselves down on couches in the kitchen to chat and laugh beneath geek-culture XKCD comics pinned to the wall. At the workbenches, one man is tinkering with a crystalline aluminum structure, lit up with diodes. Another is trying to fix the lab's homemade 3-dimensional printer, which can "print" entire plastic parts. "This is the least reliable thing on the planet," he grumbles.

A 17-year-old, still in his private-school uniform, is busy showing off a microkernel he's programmed in assembly language, a feat that would make veteran programmers blanche.

"Before this, I didn't have much social interaction outside of school," he cheerfully offers. "It's really difficult to find people with the same interests as you."

Hackerspaces, on the whole, are communal and as devoted to companionship and education as they are to material tinkering. The lab regularly hosts seminars on everything from making your own Theremin to speaking elementary Esperanto.

The Toronto Hacklab has its origins in a circle of local computer enthusiasts, many of them employed in the information-security business, who would meet to talk shop. The idea of getting their own space would come up from time to time, until finally one member, Seth Hardy, looked at rental listings on a lark. Three days later, Hardy, Wouters, and a third friend, Leigh Honeywell, pooled their money and signed the lease.

"We wanted to get it going as quickly as possible," says Hardy. "We just said alright, we'll do this."

In recent years, hackerspaces have been spreading across North America's big cities, from New York to Silicon Valley. But, Wouters says, they can trace their lineage back to post-unification Germany, when hackers began to congregate in real-world co-operatives.

"After the German reunification, Berlin was extremely poor," he says. "So you had a lot of highly skilled people and insanely cheap housing."

Hackers began to congregate in cooperatives like the Chaos Computer Club, a venerable hotbed of politics, protest, and arts. (Torontonians might recognise them as the creators of Project Blinkenlights, which lit up City Hall as the centrepiece of Nuit Blanche 2008.) And, in the ashes of a police state, Berlin's hackers were suspicious of authority and zealous about privacy.

"A citizen from the US is much more likely to say fine, you can wiretap the shit out of me, whereas a German will be much more reluctant to say that's okay," says Wouters. "Especially in geek circles, that's more and more of a concern."

These are streaks that run through hacker culture to this day.

"There's a big debate about the use of the word hacker," says Hardy, who reverse-engineers computer viruses for a living. "One side says it's somebody who breaks into computers and does malicious things. The other side says no, the word predates that and means doing creative things with devices, other than what they were intended for."

Hardy says he's worried that the darker connotation has won out. But, in the hacklab's innovative stew of politics, protest, and art, the act of creation is in the air. Quite literally, in fact; the soldering irons fuming on the workbenches give off a distinctive stink.

That redhead with the running shoes is Tom Hobson, a 19-year-old U of T student who's repurposing the shoes as musical instruments. Step down, and the shoe sends a command to the computer, which can recognize it as a MIDI signal -- that is, a note, or a drumbeat. He's already made one working pair, but they needed to be tethered to the computer with a cable, which poses obvious challenges to the ambulatory drummer.

"You should make them wireless," suggests a visitor.

"That's what I'm doing," says Hobson, poring over his circuit board. He pauses and looks up, sounding almost apologetic for a moment.

"But not super-wireless, though. I cheaped out on the radio transmitters."

Ivor Tossell is a Toronto based writer and technology columnist at the Globe and Mail.