Chartreuse Region, Second Life ? Kasi Nafus’ clothing store has bucolic surroundings. There’s a maple tree in fall colors outside, right across a brook. A little further away, a zebra munches on a bush.

If the customers arrive by foot, they have to wade through the brook. They don’t really mind, though. The water is not, in fact, real. Nor is Nafus’ clothing store. They only exist as three-dimensional representations in a virtual world called Second Life.

The clothes Nafus sells aren’t physical either – they merely cover the virtual bodies people make for themselves in Second Life. But that doesn’t mean the store, called Pixel Dolls, is not a real business. This is Nafus’ full-time job.

“It’s not something I’ll get fabulously wealthy from, but it’s a living wage,” said the 27-year-old Seattle resident. She didn’t specify her income.

An estimated 20 million people around the world are spending time in so-called “massively multiplayer online roleplaying games,” or MMORPGs. These online spaces are adding not only users, but are also growing economies that interact with the real world.

Second Life, for instance, has its own currency that is convertible to U.S. dollars at a fluctuating exchange rate. Users can buy the virtual currency using their credit cards, or sell it and get real dollars via checks or PayPal transfers.

Its 60,000 users trade $2 million a month, making its economy about the same size as that of the South Pacific island of Tuvalu. That’s small, but large enough that it supports about 100 virtual jobs, according to Philip Rosedale, chief executive officer of Linden Research Inc., which created Second Life. Some design virtual buildings, others design schemes of movement that make virtual bodies dance or perform other complex actions. There’s even a virtual journalist, though he’s employed by Linden Research.

Edward Castronova, an economist at Indiana University, estimates that real-money trading surrounding virtual worlds is at least $100 million this year, and probably many times that.

Castronova also surveyed players of the online game Everquest four years ago, and found that 39 percent would like to quit their jobs or schools and make a living in the virtual world. Multiply that by 20 million gamers, and virtual jobs start looking like one of the more popular professions out there.

Nafus says part of the reason she started making a business of Second Life was that she was practically spending a full work week on the game anyway. Designing the clothes is time-consuming: she spends a lot of time creating the “fabric” for the clothes in an image-editing program before uploading it to Second Life, where she shapes it into three-dimensional forms.

She sells her regular inventory (for instance, “Linen Tie Suit, Black”), for about $1 each, and limited editions for about $5.

Selling digital clothes is quite different from selling real clothes. For instance, Nafus doesn’t actually have to make each item, just design it. Also, the store runs itself – customers just click on images of the clothes and have copies of them transferred to their accounts.

Even so, some aspects of a virtual business are similar to the real world. Once, the Second Life computers didn’t actually transfer goods to the buyers for three days. To Nafus, it was as if the post office had lost all her shipments.

Most virtual jobs are, however, quite different from Nafus’. Second Life is an unusual virtual world in that the residents have great freedom to shape the world and create objects in it, which creates an opening for skilled professionals.

The most popular virtual worlds, however, are centered on fighting, and there’s limited scope for creativity. There are plenty of jobs there, but some of these moved overseas pretty much as soon as they were created, in what is perhaps the fastest example ever of a new job category being outsourced internationally.

“I kill monsters and things to get their items,” said Ilin Aurel, in the small town of Caracal, Romania. “It’s very fun, we love it.”

The 19-year-old, interviewed by phone, makes $200 a month, a good wage for Romania. He is employed by Gamersloot.net, which is based in Sunnyvale, Calif., to play online games like World of Warcraft and Guild Wars.

The Romanian office is staffed around the clock in three shifts with gamers (known as “gold farmers”) who collect gold and other virtual riches, which are then sold on the Gamersloot Web site to people who don’t mind spending real money to enrich their in-game characters.

“I think there’s a future in this job,” Aurel said.

The presence of gold farmers in a game is not necessarily popular among people who are playing for fun, and game publishers try to limit it, with little success.

“It’s almost impossible to design a game … that does not generate real-money trade, a secondary market,” said Julian Dibbell, a freelance journalist who supported himself trading virtual gold, weapons and “real” estate for a year and has written a book about the phenomenon, to be published next year.

“I want to say that I don’t think it could ever become a dominant sector of the economy. But look at the real economy itself … the huge, overwhelming proportion of economic transfers that take place in the world today are pure information transfers,” Dibbell said.