One school of thought maintains technology will help us transcend the physical world and create a life-like experience in the safety of cyberspace. Another says, let the computer out of the box and it will inform, control, and possibly destroy the real world humans live in. Add an artist to the mix, and you get "Displaced Perceptions: Intriguing Questions on the Desires of Uninhibited Technology," the keynote event of Web98 taking place this week in San Francisco.

Monday's keynote had four performance artists discussing their experiments with computers that crisscross the barrier between electronic and physical media, shattering assumptions about the nature of digital information.

"What we have learned is that cyberspace is immaterial. It's different from the world that we inhabit," said Natalie Jeremijenko, a performance artist who also teaches engineering at Yale University. "That is and it isn't true."

To show the current limitations of how humans experience data, Jeremijenko helped build Trigger, a mechanized horse with an engine programmed to replicate the ground motion of the 1989 Loma Prieta earthquake. This and other works seek to turn information into a physical phenomenon for people to see and experience.

Electronic data can also be immediate and directed. Berkeley graduate student Eric Paulos built floating drones that can cruise the hallways of work after hours, eavesdrop on conversations, and be used like mobile surveillance cameras. However, the drones can't open locked doors, Paulos assured an audience of 300.

The experiments pose some interesting sociological questions. For example, how does technology that enables human disembodiment challenge our privacy rights, threaten our security, or relieve us of both the authenticity of experience and the responsibility for our actions?

The Survival Research Laboratories explore issues of human responsibility in recent work using the Internet as a medium for activating lethal machinery. SRL lets people fire cement-filled soda cans from a cannon over its Web site, for instance, or destroy hundred-dollar bills, in violation of federal law. The human experience may feel virtual, but the act is very real: Participants are required to sign statements accepting responsibility for the damage they cause.

"There's nothing prohibiting people from making and [using] devices that do telecrimes and teleobliteration," said Paulos, who also works at SRL. SRL's more dramatic performances show the capability to cause mischief in spades. Demolition derby-type shows pit fire-breathing cannons against paper people. Robots destroy themselves and everything around them, sometimes even the buildings in which the events are housed.

"You wouldn't believe how loud they are," said Jill Steinberg, who attended one San Francisco show where the building's windows spontaneously exploded from the noise vibrations. "It scared the hell out of me."

The idea, said SRL founder Mark Pauline, is to make people's fears of a technological Armageddon come true in a controlled environment.

"These are manifestations of our worst possible fears of being trapped in the midst of dangerous rampaging machines, of being in the midst of technology out of control," Pauline said.

Pauline is staging several performances in downtown San Francisco this week. The first event occurred today at Multimedia Gulch's favorite lunch spot, South Park. A jet engine on the back of a flatbed truck blew into a police whistle at noon, a robot flapped its limbs and then was set afire. The artists abruptly disbanded before police and fire officials arrived. On Wednesday afternoon, a track robot, originally designed to contain and remove bombs from buildings, will grab passersby on Market Street.

Some artists bring their examination of the body-mind-technology relationship a little closer to home.

Chicago art professor Eduardo Kac injected a 2mm-by-15mm microchip into his ankle to protest limitations of the two-dimensional computer screen.

"I'm worried about the nature of the current interface," Kac said. "It confines our bodies in a way that is threatening in the long run."

Human beings start to resemble computers as they work on them over long periods of time, Kac argues. Their heads sag, their shoulders slouch; they become box-like themselves. Incorporating electronic forms into biological ones liberates the interface between human and computer, and frees digital information to inhabit more spaces than computer hard drives. But Kac isn't ignoring the fact that the integration of man and machine could also herald a totalitarian society.

The chip in Kac's ankle carries a 9-digit identification code, not unlike a social security number, that can be scanned and logged into a database automatically, effectively tracking his whereabouts.