Eng-Siong Tan had an idea for a new kind of software that could slice through national borders and create communities without regard to nationality or geography. But when it came time to put that idea into practice -- to form a company, transform the way we all relate to the World Wide Web and, he hoped, let him become a millionaire in the process -- geography suddenly mattered a great deal. As quickly as they could, Tan and his two partners moved from their national laboratory in Singapore to an Ikea-furnished warehouse here in Silicon Valley.

"This was the right place," Tan, 36, said in a recent interview in the still-Spartan headquarters of his hot company, Third Voice Inc. "We would never, ever, ever have gotten this reaction in Singapore."

Of all the claims made for how information technology will transform our lives, probably none is repeated more often than the truism that location will become irrelevant. As management philosopher Peter Drucker writes in the October issue of the Atlantic Monthly, "In the mental geography of e-commerce, distance has been eliminated. There is only one economy and only one market."

Yet the center of the information revolution is acutely rooted in its geography. "The Valley" self-consciously cultivates its own language, culture, personal networks and iconic eateries. In its celebration of entrepreneurship, Silicon Valley is as different from Japan Inc. as a business culture could be. But in their insularity, old-boy connections and celebration of their own uniqueness, the two do not seem so far apart.

Inevitably, the gap between a vision of a world without borders and the reality of geographic persistence prompts skepticism about all claims of revolutionary change. In fact, though, both phenomena -- a coming revolution and an intensely localized ground zero -- could be true.

Even the most ardent apostles of change acknowledge that, for now, physical presence counts. "There will come a time when where you are doesn't matter and entrepreneurship will proliferate across the planet," Steve Jurvetson, at 32 one of the Valley's most successful venture capitalists, told me over breakfast at the now-legendary Woodside hash house called Buck's. "But for now -- it matters."

The story of Third Voice shows how. Jurvetson first heard about Tan and his co-inventors a few months ago over a Buck's breakfast with a mutual acquaintance. He was struck by Tan's idea and set up a meeting. A few days later, Third Voice had its seed capital. "To close a big business deal, you gotta be there in person," Jurvetson says.

Guy Kawasaki, founder of garage.com, agrees. Kawasaki's company looks for entrepreneurs with promising ideas and then sends investors their way. So far, he has anointed 40 promising candidates out of about 7,000 that have come calling. Two-thirds of the winners are in the Valley -- and the others are desperate for Valley ties. "They want Valley money because it's more connected, smarter," Kawasaki says. "Not all dollars are the same."

Third Voice is now up and running with about $5.5 million in Valley dollars. Its software allows users to post comments on any Web site -- whether that site welcomes them or not. The comments are visible only to others who choose to use the same Third Voice software and who can then add their own comments, allowing for uncontrolled dialogue at any site on the Web.

Tan says his company could alter not only a user's relationship to the Internet but the very essence of the human experience of reading. "The way we read today, there's the author's voice, and your own voice in your own head -- that's the second voice," Tan explained to me. "So now we add a third voice."

That kind of expansive assertion is standard fare here. "This whole Internet thing -- it's bigger than the Industrial revolution," Mike Volpi, a vice president at Cisco Systems, told me. "It changes everything." Volpi is only 32 years old, but Craig Barrett, president of giant Intel and himself a grandfather, has no doubts, either. "Of course the Internet changes everything," he says.

It's easy for an East Coast skeptic to dismiss such claims. But the explosive acceleration of change, in both the physical and virtual worlds, makes the claimants seem almost conservative. Volpi's Cisco Systems is adding 2,000 employees every quarter. Two years ago, yahoo registered about 6 million page views per day; today it gets more than 300 million, close to a third of those from outside the United States, according to vice president Ellen Siminoff. Geography still matters, but the culture of knowledge-based entrepreneurship is spreading -- to Austin, Boston, Northern Virginia, Israel.

More to the point, according to futurologist John Seely Brown of the Valley's Xerox Palo Alto Research Center, the question of geography itself may be out of date. Two years ago, he said, people were asking to what extent the virtual world would replace the physical. "But the real question is how each can complement the other," he said, envisioning "a new kind of product that sits on the boundary between the virtual and physical worlds, with tentacles in both."

Having trouble imagining such a product? Of course you are. You don't live in the Valley.