Virtual sex can be very unsatisfying. That's why Kevin Alderman invented the SexGen, a cyberworld bed that allows video game characters, or avatars, to engage in more than 150 virtual sex positions.

Alderman claims he's sold 100,000 of the virtual devices at $45 a pop to residents of Second Life, the popular online pseudo-world.

Now, Alderman is suing someone -- or, really, something: an avatar named Volkov Catteneo -- for ripping him off. Alderman claims in a copyright-infringement lawsuit filed in a real federal court in Tampa, Florida, that the defendant he/she/it (a.k.a. John Doe in the complaint), copied SexGen and began selling it at cut rate prices.

Nearly 8 million people use Second Life, which was created by Linden Lab in San Francisco. They do so by creating avatars, or virtual representations of themselves. Perhaps not surprisingly, many of them spend a lot of their time in pleasurable pursuits including virtual sex.

There is little legal precedent for suing an avatar. But the spat over a virtual sex toy could mark a milestone in how real world courts decide virtual intellectual property disputes.

In Second Life, one U.S. dollar trades at about 270 so-called Linden dollars; its virtual economy is estimated to generate a $64 million G.D.P.

Last year closely held Linden said it received an $11 million injection from Amazon.com founder Jeff Bezos and Globespan Partners, Benchmark Capital and others.

Alderman, whose avatar is called Stroker Serpentine, is an entrepreneur in the Tampa suburb of Lutz, Florida, who recently gained notoriety for selling a virtual red-light district modeled after Amsterdam on eBay to Dutch media firm Boom for $50,000.

He told a correspondent in Reuters' Second Life bureau (don't ask) that his company, Eros, has sold as many as 100,000 copies of the bed at issue in his lawsuit. At $45 in real-world money for each SexGen (as he calls the beds), that adds up to a going concern.

Although copyright disputes involving online intellectual property such as music and movies are common, this case has a few unique wrinkles, notes Wagner James Au writes on the GigaOm blog.

"The contention is over a virtual sex bed which doesn't exist, and the named defendant also doesn't exist," Au wrote. "As such, the suit will establish an enormous precedent in the new realm of virtual world law, however it shakes out."

Second Life's booming business environment has attracted attention from some members of Congress. Ever on the lookout for new revenue sources, they are preparing to hold hearing about taxing virtual income earned in online communities. For now, Second Life is the virtual equivalent of the Wild West. And like Dodge City, the liveliest trade is in vice, particularly virtual sex, which is where Kevin Alderman comes in.

"SexGen, which is our best-selling animation system -- it's what we built our business on -- was a combination of ideas and collaboration between a programmer, an animator and a pervert," Alderman told Wired.

He described himself in another interview as "a toy maker, an erotic Geppetto," and his web doppelganger Serpentine as "a pervert at large. Erotic facilitator. Pornographic mogul."

Alderman's lawsuit seeks to identify the real life person behind Second Life avatar Volkov Catteneo, who is alleged to have ripped off the design. And a federal judge has allowed Alderman's lawyer to subpoena financial records from Linden Labs and Pay Pal in order to unmask the alleged infringer.

In a Second Life "interview" with Reuters, Catteneo sounded a defiant note.

"My name isn't on [Linden Lab's] file," he said. "I don't even have a permanent address [in real life] either."

by Sam Gustin