a product that doesn't really exist and sell it for actual money? Who would buy property that is nothing more than a collection of pixels? And who would exchange real American dollars for virtual money to be used in a virtual world, to be given to virtual people to buy virtual things?

Lots of people would. Millions of people have found value in a virtual existence, and millions more will follow suit in coming years. From virtual shopping to virtual friendships to virtual lovemaking, many people are deriving real benefits from virtual places.

The phenomenon of virtual worlds is all around us. There are hundreds of MMORPGs. For example, World of Warcraft (WoW), an expansive fantasy world of elves, wizards and warriors, boasts a population of nearly 9 million users. Other MMORPGs, such as Ultima Online, Everquest, and World War II Online bring hundreds of thousands more users to the virtual table.

Other virtual worlds are designed for more practical tasks. Take Microsoft's Virtual Earth. Instead of creating a fantasy world, Microsoft is building a virtual replica of the world we exist in now. Earlier this year, at the O'Reilly Emerging Technology conference in San Diego, Calif., Microsoft Virtual Earth general manager John Curlander presented a compelling look at the future of realistic virtual worlds. Curlander showed videos of fully rendered cities, including Philadelphia and New York. The cities were presented from an immersive, three-dimensional perspective. Some 50,000 structures, complete with accurate exteriors, made it feel as if the real Philly was up on the projector screen.

In a follow-up interview, Curlander discussed some of the ways governments might use Virtual Earth.

"The data quality is high enough that it meets a large percentage of the applications that an urban planner or any city user would need," he said. "They won't need to have custom flights done to collect their data. They won't need to have custom processing done to create their products. They can simply access the Virtual Earth databases through our viewer and get most of what they need from that -- if not all. Potentially it's a huge savings for cities to be able to access these kinds of databases and not have to commission them themselves."

While not as enchanting as Second Life, urban planning is vital to the well-being of a community. Additionally emergency response, homeland security and even tourism could reap benefits from Virtual Earth.

"We have a lot of inquiries from cities -- police departments, fire departments and so on about the data and using the models," Curlander said. "With accurate, detailed 3-D models of cities, that's a valuable asset for emergency responders."

Microsoft's goals for Virtual Earth are lofty. The company wants to render all major population centers in exquisite detail. In fact, Curlander said the plan is to distinguish one brownstone home from another. Having this level of detail could, for example, help firefighters find the best avenues to rescue a trapped victim.

"I think if you talk to emergency responders, they would say having that kind of detailed knowledge would be incredibly valuable -- including knowing where the windows are and other kinds of structures that might impede a vehicle from getting close to the building," Curlander said and, in a nod to Second Life, added, "What we're building is the 'first life' -- we're building the real-world framework."

That real-world framework will, for now, take some tremendous computing muscle -- a fact Curlander readily admits. But he said there are plans to host some of the burden so users can realize the power of a highly detailed, 3-D world.

Chad Vander Veen  |  Editor, FutureStructure

Chad Vander Veen is the editor of FutureStructure.com