When inventor-activist Joshua Kinberg got nabbed on the eve of the 2004 Republican National Convention in New York City, he was in the midst of an interview with MSNBC's Ron Reagan.

Kinberg was describing a device he'd dubbed Bikes Against Bush. The concept was as subversive as it was simple: Visitors to Kinberg's Web site (www.bikesagainstbush.com) would type short invectives (no obscenities allowed) about the current administration, which were to be transported to a laptop mounted on his bike, and then, as Kinberg pedaled down the block, an array of spray cans filled with water-soluble chalk would 'print' his favorites on the street. The New York Police Department was not amused.

Before Kinberg got to demonstrate the invention, he was arrested for criminal mischief and his Wi-Fi-enabled bike, laptop, and souped-up dot matrix printer were confiscated -- all while the MSNBC cameras rolled.

At press time, the NYPD had yet to relinquish his equipment, but the publicity Kinberg received during and after the arrest was more than a welcome consolation prize -- it was an anticipated outcome.

Kinberg is part of a high-tech political movement involving artists, scientists, activists, and inventors who are blending technology with street theater, both to draw the public into the creative process and to ensure that the art of protest keeps pace with the mass media.

To do this sort of improvisational performance art requires props -- functional high-tech accessories that attract attention. Dozens are already available to the public, and countless others are in development. Here are six of the most subversive:

Magicbike Wi-Fi Bike: It's true that wireless Internet connections are everywhere, but when you're running from police at a NAFTA demonstration, it's not always so easy to pop into a Starbucks to get wired. The Magicbike, equipped with Wi-Fi antennas that feed into a laptop located in a specially equipped saddlebag, can keep up to 350 people connected to the Internet anywhere wireless access is needed. Artist Yury Gitman says his creation has a reach of up to 100 meters. www.magicbike.net/about.html

Rocket Crowd Counter: Official crowd counts done at protests, especially counts conducted by local 'officials,' are notoriously low. To circumvent the system, the Bureau of Inverse Technology put a tiny video camera on a model rocket that, after popping its parachute, sends footage back to computers on the ground that are equipped with head-counting software. http://www.bureauit.org/rocket/