Janne Valkealahti peers at his cell phone and presses a few keys, swiftly dumping about $14,000 of stock on the Helsinki exchange. Thanks to his phone's wireless connection, Mr. Valkealahti is invisibly tethered to the Internet and to the Web site of eQ Online, the brokerage house where he works.

It's an impressive demonstration, but then this is Finland. Last year the nation found itself anointed the Silicon Valley of the wireless Web, and it has been basking in the glow ever since.

Fueled by incredible cell-phone usage -- nearly three out of four Finns carry one -- and the presence of phone maker Nokia, start-ups here are working to put the Web everywhere, and get rich too.

Finland's wireless wizards dream of blazing a new online frontier that will turn their start-ups into global giants. Indeed, last week's megamerger deal between Mannesmann and Vodafone AirTouch was driven by the potential of a wireless Web.

But even as the world hails Finland as ground zero for the wireless revolution, some of its entrepreneurs are already asking themselves: for how long? The answer will make or break a few embryonic fortunes. It will also indicate to what extent the Web has already fallen irrevocably under the sway of a few U.S. companies that grabbed early leads.

One of the stars of Helsinki's start-up scene is Jari Ovaskainen, the founder and CEO of Iobox Oy. His ambitions are nothing short of staggering. "We expect to be mentioned in the same breath as AOL and Yahoo!," says Mr. Ovaskainen in his office a few blocks from the Mannerheimintie, a main thoroughfare in Helsinki's city center.

In fact, Iobox expects to be the Yahoo of wireless phones. The company operates a Web portal uniquely tailored to the needs of mobile Net surfers.

More than 400,000 people use it to check their calendars, read and write e-mail and even order compact disks.

Iobox is quickly leaving its Finnish roots behind. Though research and development will remain in Helsinki, the company's headquarters is moving to London, a beachhead from which Mr. Ovaskainen and his colleagues hope to dominate one European market after another. "Our goal is, when you think mobile, you think Iobox," he says.

To truly appreciate the future envisioned by Iobox and the others, you need the latest phone. The hot one here now is the 7110 model introduced last year by Nokia. It uses WAP, the Wireless Application Protocol standard, to zap Web content around. The phone is a distinctive forest green and has a tiny screen that can display Web menus and stock charts. Though the phone is still in short supply, nearly every high-tech executive I visited in Helsinki had one.

Hannu Bergholm uses his to show off one of the more popular wireless applications in Finland, a service that beams jokes onto phones. Swedish jokes, to be specific. "How many Swedes are needed to have sex?" reads Mr. Bergholm from the phone's screen. "Answer: three.

Two are doing it, and the third is reading the manual."

Mr. Bergholm is the managing director of Wapit, a start-up that's developing systems to take standard Web content and easily beam it onto WAP-enabled phones. The company is known for both its wireless services and its co-founder, Mato Valtonen, a longtime member of the Helsinki rock band Leningrad Cowboys, Finland's answer to Spinal Tap.

Mr. Valtonen says he knows Wapit's fate may be acquisition by a U.S. company. So do the programmers the company recruits. Mr. Valtonen says job candidates routinely ask if Wapit plans to sell out soon. But, he adds, "we have a dream. We are not building this just for someone to buy it out."

That's probably not realistic for most start-ups, though, says Juha Mikkola, a veteran venture capitalist at Eqvitec Partners Oy. "We have a first-mover advantage against the brands that dominate the Internet, but only for a few months," he says. "Not years. Months." Mr. Mikkola says he expects that U.S.-based companies will soon swoop in and use their high-priced shares to buy up key Finnish start-ups.

William Cardwell, a Lynchburg, Va., native transplanted to Helsinki to form an alliance between Eqvitec and Robertson Stephens, agrees.

"Most entrepreneurs will publicly tell you they're on an IPO track," he says. "But they're practical -- if the acquisition comes along, they'll take it."

His goal, he adds, is to make sure that when Finland's fledgling Net ventures are bought, they get the highest prices possible.

Meanwhile, Finland's wireless-Net community keeps churning out cool new applications, such as the machine that lets you buy a soda by dialing numbers on your phone, automatically charging the beverage to an account.

Other ideas with lots of buzz: wireless access to online auctions, m-commerce ("m" as in "mobile") and so-called location-based services.

These services would use the cell-phone system's ability to pinpoint your position and then display relevant Web content -- say, the closest restaurant or parking lot.

Then there are old standbys, like games. A new venture called SpringToys is developing Internet games for mobile phones and expects to move into gambling. Janne Turunen, its vice president, says it's already in talks with the Finnish national lottery regarding bets on hockey games. "Phones are toys here in Finland," he says. "We are trying to make them toys everywhere else, too."