IMAGINE you're in a futuristic world. Strapped into the front seat of a spaceship, you are launched into a high-speed chase through narrow canyons, cities, and the unknowns of outer space.

It feels real, but it's not.

Welcome to "The Other Side: A Virtual Reality Arena."

Here at Boston's World Trade Center, organizers tout the collection of amusements as the first of its kind, with state-of-the-art equipment in interactive entertainment, motion simulators, virtual-reality attractions, computer-generated environments, and special effects. It can be described as a combination arcade, amusement park, and science museum.

Although such simulation-adventure and virtual-reality games are offered in other places, organizers cite this event - which will begin a national tour in October - as unique.

Rick Velardo just went on a dog sled-snowmobile-bobsled adventure with "Freedom 6," Omni Film's motion-based adventure theater. "It's better than I expected," he says. The wraparound large-format screen, along with the seat platform that sways in sync with the film, makes the experience realistic. "I got sweaty; I didn't know if I was going to make some of those corners!" he says.

Possibly the most popular attraction at "The Other Side" is "Chameleon," an interactive ride that simulates race-car driving and the flying of an F-117 Stealth aircraft, right down to the gravity force.

Marc Ross, chief executive officer of Chameleon Technologies, says the goal is to "experience something that you would not ordinarily be able to experience." So it follows that he's not talking about something as passive as a simulated roller-coaster ride. You drive the race car or fly the F-117 yourself by watching a computerized screen. It feels real.

No wonder. Mr. Ross's parent company - Veda International - has spent nearly 31 years as a contractor for the United States government and the Department of Defense. "The technology that was needed to develop 'Chameleon' came out of some of the technology we developed for fighter pilots - to train them for the military," Ross says. Because of military cutbacks, a handful of companies like Veda are looking toward the leisure-entertainment market to diversify.

"The more realistic the simulator, the better," Ross says, noting that some so-called virtual-reality experiences can get boring if the person eventually figures out what's going to happen next. Genuine interactivity is key, he says.

The definition of virtual reality is somewhat loose. Some people use it to describe anything that makes an experience more real. Others, such as Ben Delaney, publisher and editor of CyberEdge Journal, based in Sausalito, Calif., insist it must be a computer-mediated experience involving three-dimensional graphic models, 3-D sound, random interactivity, and a realistic setting.

The concept of virtual reality is not new. The Defense Department and NASA have long used simulation, and more recently adopted virtual reality as their training method of choice. NASA, for example, is using virtual-reality technology to train astronauts to repair the Hubble telescope. Engineers, surgeons, and other professionals use it to visualize procedures - such as designing an airplane or a restaurant before building even starts.

"The Other Side" arena is testament to the fast-growing interest in virtual reality for entertainment.

In the "Iwerks Reactor," for example, a visitor is on a mission with Robocop to save the mayor. When you "pop a wheelie" on the police motorcycle, your seat actually tilts back. When you speed down a ramp, you go forward. When you smash through a bunch of barrels, the sound is almost deafening. It's like a comic book come to life.

Horizon Entertainment's Virtuality offers the game "Dactyl Nightmare," another popular attraction. A "visette" is placed over your head and you're immersed in a virtual environment, shooting at enemies and pterodactyls from above. You can pivot around 360 degrees.

Manufacturers and designers are the first to admit that virtual reality still has a long way to go. As the technology advances, there may be a time when the screen for interactive experiences will be less video imaging and more lifelike, for example.

Ross says: "We think eventually - when the new-generation computer chips come out - we'll be able to compress film, and that'll be the ultimate."

This year, the spending for virtual-reality equipment is expected to be around $250 million, according to CyberEdge's Delaney.

"All the major game manufacturers are announcing virtual-reality types of games," Delaney says. "It's going to be really big." He compares virtual reality now to where personal computers were in the late 1970s and early '80s: "Ten years later they were everywhere," he says.