THE PLAIN BROWN WRAPPER

of the 21st century comes with a tiny screen and headphones.

After Apple Computer added video capability to the iPod last month, its iTunes store needed 20 days to sell a million episodes of hit ABC shows under a licensing deal with Walt Disney.

But Disney's "Desperate Housewives" have nothing on SuicideGirls.com, which took just a week to distribute a million free podcasts of its considerably pierced and tattooed amateur models, according to the Washington Post.

Portable, digital pornography is already a big business in Europe and Asia, where many cellphone users are as comfortable wirelessly downloading smut onto their cellphones as Americans are writing it onto their hard drives. Now the advent of sleek handsets with high-resolution screens is popularizing the porn-to-go trend in the U.S.

AVN, the U.S. porn industry's leading trade journal, pegs domestic sales of mobile adult content at just $35 million annually, compared with $2.5 billion for Internet porn and $12.6 billion for the industry overall. AVN pegs global mobile sales of adult content at a juicier $700 million.

The U.S. market for wireless titillation could reach $1 billion by 2008, according to the Yankee Group, a Boston technology consulting and research firm. That's peanuts for giants like Apple and Disney who are at any rate unlikely to diversify into the field but a potential bonanza for adult-content purveyors such as Playboy Enterprises, New Frontier Media and Private Media Group, not to mention numerous closely held rivals.

"There's no question that this part of our business is ready to explode," says Steven Hirsch, CEO of Vivid Entertainment Group. The Los Angeles-based company notches revenues of some $100 million a year by producing and distributing such films as "Bare Naked" and "Happy Ending."

Vivid now offers a $24.95 monthly subscription that includes podcasts of its movies, and expects that mobile content will make up at least 30% of its business once it becomes widely available, which won't happen until wireless service providers work out reliable procedures for blocking sales to minors.

Playboy has also gone portable. Two weeks ago, it announced the launch of its Playboy Bodcast, on which bikini-clad models dispense the mildly racy wit and wisdom of octogenarian Playboy founder Hugh Hefner. It's seen as a trial balloon for a subscription service that might offer more explicit fare.

Playboy has leveraged its flagship magazine into a global lifestyle brand, while branching out into cable pay-per-view and broadcasting. Its web properties are now drawing 2.5 million unique visitors a month. CEO Christie Hefner, speaking at recent media industry conferences in New York, said the company would soon start breaking out its mobile content numbers in earnings releases.

"As you've already seen with the iPod, new media platforms are driven by a desire for music, games and adult content," says Playboy Entertainment President Jim Griffiths. "We really think that's an opportunity for us. But the model is still too new to make predictions."

For Playboy, content is indeed king, with entertainment division revenues helping to push its stock up 8.3% for the year, despite a projected 75% drop in earnings per share after a big restructuring charge. Revenue is expected to rise 3% to $341 million in fiscal 2005, according to the Thomson First Call consensus.

Much of the initial growth in Playboy's mobile business is expected to come from overseas, where the company has already signed a deal with Hong Kong cellular service provider Hutchison Telecom International, according to Robert Routh, an analyst with Jefferies & Co. "At this stage, it's too early to quantify the impact," he says. "The content is already there, and it's not expensive to reposition it and distribute it through a different medium."

The other publicly traded skin merchants have not fared as well in the stock market this year, hurt by their reliance on cable pay-per-view amid rising competition in that area. New Frontier is down 18.1% year-to-date. Private's thinly-traded stock has dropped 44.7% for 2005.

Private, the European producer of sexually explicit films and magazines, also sells its content over the Internet and cellphones. Spokesman Gary Thoulouis says the company plans to sell podcast subscriptions sometime next year.

Barcelona-based Private posted revenue of $7.5 million for the three months ended Sept. 30. Of that, $576,000 came from mobile sales, and that's after a 50-50 split with the wireless service providers, according to wireless technologies director Tim Clausen. He says Private can boost its 2006 mobile revenues to three million euros, or $3.6 million.

"I see mobile as one of our biggest revenue pillars," Clausen says. "We are going to make money with mobile, with video on demand and Internet sales. And make less money selling DVDs and magazines in the classical way."

Although the stock is listed on the Nasdaq, the Private brand is relatively unknown in the U.S., which Clausen says may be a matter of, um, taste. "We don't do American content," he says. "We don't have those blonde girls, the classical American ones with fake boobs. We keep it a bit more natural when it comes to the content we show."

Cultural preferences notwithstanding, the taste for wireless adult content is universal, say industry players. Harvey Kaplan, director mobile operations at Xobile, a unit of the privately held Adult Entertainment Broadcast Network in Charlotte, N.C., says there's every indication that customers will ring in the risqu as soon as they have the option. The company sells two-minute clips for video-capable cellphones at 44 cents each, and provides video on demand for 8.5 cents a minute.

Kaplan declined to release revenue figures, but says the mobile business is growing almost 50% faster than the Internet side. "Anyone who's in the adult marketplace and believes that the Internet is the be all and end all is sadly mistaken," he says.

But the Internet remains the delivery channel of choice for podcasts, and content providers taking this road don't need to worry about paying tolls. Eric Wold, an analyst who covers New Frontier for the San Francisco investment bank Merriman Curhan Ford & Co., notes that the company keeps just $1.50 of a $10 viewing fee for one of its films on cable. Mobile content revenues are split 50-50 between the provider and the wireless network operator. But the podcaster doesn't have to share.

"This could be pretty profitable," says Wold. "The cost of putting this content into a format to put it onto a new device is pretty minimal."

The flood of tiny explicit images might well have a transformative effect on public conduct. Steve Coulson, who runs PodGuide.tv and YesButNoButYes.com, a pair of blogs dedicated to video content for iPods and popular culture, respectively, says he's seen about 15 dedicated adult sites crop up since the video iPod was released.

A friend of his recently sat next to an iPod owner enlivening the train ride with a little on-screen skin. "If it had been me on that train, I'd have gotten up and walked across the aisle," says Coulson.