Since April, baseball fans attending San Francisco Giants home games at SBC Park have enjoyed wireless internet access if they bring a portable computer with them. The stadium is one big wireless Internet, or WiFi hotspot. And news reports say that next season, the service will be upgraded, so that fans will be able to get instant replays of action on the field displayed on their computers, right at their seats.

On the other side of the country, Philadelphia, Pennsylvania, the nation's fifth-largest city, is probably best known here as the place where America declared its independence from Britain in 1776. But today, leaders of 21st century Philadelphia want to declare freedom from wired internet access and are looking to position the city as a technology innovator.

Earlier this month, Mayor John Street appointed a committee to investigate the feasibility of blanketing the entire 350-square kilometer city with WiFi Internet access. The city's chief information officer, Dianah Neff, explained that the project has potential social and economic, as well as technical advantages. "The Wireless Philadelphia initiative is a technology opportunity that we believe will promote Philadelphia as a technology city but, more importantly, it positions Philadelphia to be a digital city that addresses economic development, social development, as well as helps close the 'digital divide', " Ms. Neff said.

The digital divide refers to the gap between educated and affluent people who use computers and the Internet, and disadvantaged people who don't.

"Because we compete in a knowledge economy, it is important that all residents have the opportunity to participate," said Dianah Neff. "Not all segments of our city have access to high-speed broadband [Internet access], which we believe is as necessary to be competitive in this knowledge economy."

Wireless Internet access - the technology is called WiFi - is becoming more and more common in public places. Coffee shops are popular WiFi hotspots, where users can stop for a drink while using their laptop computers to send an e-mail or check a movie schedule. Public libraries are starting to offer WiFi access to patrons. Some businesses use it so workers can move from their office to a colleague's, or to a conference room, while staying in touch with the company's computer network.

The new proposal would greatly expand an existing program, which provides Internet service in a few locations in Philadelphia. The city's chief information officer, Dianah Neff, explains how the current system would be a model for the proposed citywide project.

"Well today, we actually have hotspots," she said. "For example, in our JFK Plaza - Love Park, as it's called - we have a free wireless [service]. So anybody with a laptop or a handheld device can go into the park, register, and for free connect to the Internet and, you know, check e-mails, make reservations, get access to information."

An estimated 200 or more local governments in the United States are at least investigating the possibility of using WiFi wireless Internet throughout their jurisdiction. Most are planning to restrict it to official use.

"We believe Philadelphia is the first major city to look at doing it citywide and providing that service and making it available to non-profits and education - both the school district and the universities - as well as our businesses," continued Dianah Neff. "And we're working with our minority chambers [of commerce] to do focus groups to hear what the business needs are of the small and disadvantaged businesses."

One limit of the Wireless Philadelphia proposal, says Ms. Neff, is that it aims to provide Internet access to outdoor areas, not inside everyone's house or place of business.

"Right now, what we're doing is, if you think of it as a road, when you built the roads to get you to places, it will get you to your home, but it doesn't take you into your home," she said. "So right now we're building the infrastructure that covers the entire city that is outdoors. It's 802.11bg technology that is meant for coverage outdoors. However, depending on where you're located, there will be some bleed-over. You can come out onto your porch and get the free access. There are also companies that are making devices that you put on your window and you can bring it indoors."

Officials are in talks with Internet service providers, who worry that the city may be cutting into their business. Meanwhile, Philadelphia Chief Information Officer Dianah Neff stresses the revolutionary possibilities of WiFi internet service throughout her city.

"This is a technology that can be as transformational as the World Wide Web was 10 years ago," she said. "We've had the ARPANET/Internet for many, many years, but it wasn't until there was a tool that allowed massive use and ease of use that it truly changed our lives. And I think this is the next technology that can be of a societal benefit to all areas and people, and we look forward to being a part of that."

The Wireless Philadelphia program is projected to cost about $10 million. City officials hope at least some of that money will come from private sector investors or business partners.