A FEW minutes into the opening reception for an exhibit on the intersection of design and technology at the Chelsea Art Museum, one of the pieces caught fire. The installation, called “Saws,” accidentally ignited when one of the work’s three chainsaws became caught on a stripped extension cord that dangled over a metal sheet on the floor.

Propelled by smoke and dust, the crowd emptied out onto West 22nd Street, where they were met with another curious sight. An oversize tricycle was rounding the corner, weighed down with a video camera, a laptop computer, a digital projector and, attached to its frame with bungee cords, two loudspeakers playing “Doobie Ashtray” by the Houston rapper Devin the Dude.

The cyclist was a 30-year-old robotics engineer named James Powderly, who, among other projects, once helped develop a remote-controlled arm for NASA’s Mars rover program. Alongside the cycle walked Evan Roth, a 28-year-old artist whose graduate thesis at Parsons the New School for Design analyzed graffiti tags as a source of mathematical data.

In the fall of 2005, the two formed an entity called the Graffiti Research Lab, a nonprofit design studio with the mission of producing tools for urban communication. The cycle is their latest invention, and its appearance in Chelsea was its official New York debut.

As Mr. Powderly neared the museum’s entrance, he jumped off the cycle and pointed it toward a bare stretch on a garage door across the street. Mr. Roth pulled a laser pointer from his pocket, and as he moved the laser’s green dot across the wall, a line of what looked like thick, drippy paint lit up its surface, roughly following the motion of his hand.

But what seemed like an illegal tag was in fact a projection, an ephemeral splash of digital graffiti that would vanish with a flick of a switch on the cycle’s gas-powered generator.

“You want to try?” Mr. Roth asked the growing crowd behind him. He handed the laser pointer to a young woman standing nearby. She nodded, hesitant but curious.

The cycle is designed to be an accessible, almost playful simulacrum of street tagging, giving passers-by a whiff of the thrill of posting a message in places they’re not supposed to. It is what its creators call a gateway graffiti experience. The idea is to put the tools for unfiltered, unsanctioned public expression in the hands of those who might otherwise shy away from grabbing a spray can or a paint marker.

By night’s end, several dozen people had used the laser to scribble personal messages, squealing with amazement each time the projected beam of light appeared on the wall.

Open City is an exhibition about the tools and methods employed by graffiti writers, street artists, activists, and pranksters. Come drink free beer and watch videos of people break'n da law. Video documentation and tools by the following artists will be on display:

laser pointer + projector on giant building = immense graffiti

video and some text that doesn't explain much.

also - a tricycle w/ speakers attached for roving street parties 

Devising digital techniques for graffiti artists

By Geeta Dayal The New York Times Published: June 23, 2006

NEW YORK This city may have given birth to modern-day graffiti art, but how is it keeping up with the times?   Graffiti in its traditional form, involving aerosol cans of spray paint and an inviting flat surface, still dominates on the streets. But online things are evolving quickly.