Illustration by Anton.

Once a week, Tim Dressen of the Twin Cities suburb of Roseville, Minn., sits in front of his computer and talks, for 20 to 30 minutes at a time, about Las Vegas.

About hotel mergers. The monorail. Oscar Goodman. Travel tips, buffet reviews, tidbits he's gleaned from online versions of the city's papers. About, pretty much, whatever occurs to him.

Then Dressen types a few commands into his computer. A few minutes later, hundreds of people will be able to check their computers and find Dressen's self-produced radio show waiting for them.

Some will listen to Dressen at their computers, but others will transfer his words to their iPods or digital music players and listen to what he has to say while they're running on a treadmill at the gym, driving to work or puttering around the house.

Pretty impressive, really, for a guy who's invested all of 400 bucks or so in creating his own miniature media empire.

Dressen is creator, host and producer of a podcast called "Five Hundy by Midnight," and one of a growing number of do-it-yourself not-technically-broadcasters who are riding the first wave of what's either an absurdly over-hyped fad or the beginnings of a revolution in how we listen to the radio.

Definitions of podcasting -- the word's most likely a mashup of iPod, Apple Computers' popular digital music player, and broadcasting -- can sound profoundly nerdy. But what it all comes down to is recording an audio file on a computer and then making it available to anybody who wants to listen to it.

That's done through software installed on a listener's computer that searches out and automatically downloads the file whenever it becomes available. The listener then downloads it onto an iPod or similar device and listens to it whenever and wherever he or she wants to.

It's easy, goofproof and automatic -- kind of, as the popular verbal shorthand goes, like TiVo for radio.

Even by computer-world standards, podcasting is new. In fact, the software required to make subscribing to podcasts effortless became widely available less than a year ago.

Then, in June, podcasting entered the mainstream when Apple Computers incorporated into its latest version of iTunes -- the popular digital music management program that feeds music to iPods -- the ability to subscribe to podcasts with the click of button.

Apple says iTunes customers subscribed to more than 1 million podcasts during the first two days of the software's release. Dressen's own "Five Hundy by Midnight" -- the name comes from a line of dialogue in the film "Swingers" -- has been listed in iTunes' podcast directory since Day One and, Dressen says, "the effect has been huge."

Dressen says the number of downloads for each show has doubled, from about 350 to 700, since the new iTunes software was unveiled, and he's received "tons of e-mail" from listeners who say they discovered the show through iTunes' podcast directory.

Like many, maybe most, podcasts, Dressen's podcast is charmingly quirky. "Generally, I talk about pretty much anything I'm interested in that's related to Las Vegas," Dressen explains.

Dressen has opined about the Caesars-Harrah's merger, reviewed buffets and discussed his fascination with Norm Clarke's Vegas Confidential column. And Dressen says he was surprised that a "sound scene" tour he did of the center Strip -- he slapped a microphone onto his iPod and walked from The Venetian to the Barbary Coast, describing what he saw and recording ambient sound along the way-- was so popular among his listeners.

For Dressen, podcasting is a hobby. For Jimmy Diggs, owner of LVRocks.com, an Internet radio station that provides airtime studio and production facilities to Webcasters, it's another way fans of "DailyNoise.com" can listen to the raucous daily talk show.

The program's Web site always has offered archived audio files of each show, Diggs says. But, now, listeners who miss the live Webcast can download podcasts of each show into their iPods or digital music players to listen to at their leisure and without having to sit in front of their computers.

Diggs says the Webcast has 3,000 to 5,000 listeners on a typical day. Now, about 1,000 podcasts of the show also are downloaded each day, says Diggs, who estimates about 75 percent of those downloads are being accessed by new listeners.

John Iasiuolo broadcasts his program, "Computer Outlook Radio Talk Show," daily on KLAV-AM 1230. About eight weeks ago, he began offering podcasts of the daily show, too, and figures he's picked up about 30,000 listeners through the podcast alone.

"It's put my show in front of a lot more people," Iasiuolo says.

Just over a month ago, the International Church of Las Vegas also joined the podcsating universe, adding podcasts of sermons to a multimedia ministry that also includes a weekly television show and archived audio files of sermons on its Web site.

"From what we can tell, about 142 people have subscribed," says Ryan Cooley, the church's associate director for multimedia. "That's with very little promotion. We just put it in podcast directories and haven't really promoted it much, even within the church."

The podcast-ready version of iTunes has been "one of the biggest draws to our Web site, just because it's so much easier (to subscribe) now," Cooley adds. "Before it was kind of a nerdy thing. You had to have a (third-party) program to do it. But a lot of people are familiar with iTunes, and you just have to have the ability to click on it."

For listeners, part of podcasts' appeal is their sheer variety. From astronomy to board games to political commentary, there's a podcast for just about everybody. And, sometimes, podcasts can make for strange thematic bedfellows.

Take Las Vegan Shaun Daily's Webcast and, since June, podcast, "Subject2Discussion," that is a forum for followers of both politics and the sci-fi TV series "Battlestar Galactica."

"I do my (political) show and, at the end of the show, I do 'Battlestar Galactica' " Daily explains.

Daily says he averages about 5,000 listeners per show, and that the podcasts have about doubled his listenership. He's received e-mails from Australia, Britain and South Africa, where, Daily says, a man wrote that "he listens to the podcast on the way to and from work."

Newcomers sometimes ask "what kind of show is this?" Daily concedes. "I say, 'Hey, it's my show. I can do whatever I want with it.' "

If podcasters have a credo, that'll work as well as any. Dressen says the creative freedom podcasting offers represents a liberating alternative to commercial radio.

"I was an absolute radio freak as a kid. I would say that, growing up, I had aspirations to be on the radio," Dressen says. "Now, over the years, radio has, I'd say, become increasingly homogenized, with essentially the same programs on every station in every city. So, I've pretty much quit listening.

"Then, suddenly, here in the past year, along comes a vehicle for pretty much anybody to produce a radio-style show, and radio becomes exciting again."

"It's very cheap to start," Dressen continues. "I think most podcasters start with a pretty basic setup of, like, a $15 computer mic and free audio editing software. And, once they get hooked, they start building up on it and end up spending a little money on mixers and things like that."

Sue Carpenter knows about low-budget radio. Carpenter, now a feature writer at the Los Angeles Times, once was a bored law office receptionist who ran pirate radio stations in San Francisco and Los Angeles.

Carpenter, who wrote about her pirate radio days in the memoir "40 Watts From Nowhere: A Journey into Pirate Radio," says podcasters and pirate broadcasters probably have similar motivations for doing what they do. In part, she says, it's about using radio as a means of creating a community.

"When radio works, it's magical, and you just feel something special is happening," says Carpenter, who now follows podcasting as a reporter. "And I'm sure people who are involved with podcasting get that same sense as well. For me, pirate radio also had that."

But, already, podcasting is showing signs of being sucked into the mainstream. Exhibit A: Radio giant Clear Channel now offers podcasts of content culled from 25 of its over-the-air stations.

Clear Channel spokeswoman Jennifer Gery says that, since June 6, Clear Channel Radio "has delivered 1.3 million pieces of content via podcast download or stream" as well as about 350,000 podcasts a week through Apple's iTunes Music Store.

However, Gery says none of Clear Channel's four Las Vegas stations are offering podcasts yet.

Fans of National Public Radio will find many public radio stalwarts available as podcasts, too. Podcasts from NPR affiliates in California and New York are offered via iTunes, while Audible.com, an online merchant of audio books and podcasts, offers subscriptions to such public radio staples as "Car Talk."

Flo Rogers, director of programming and assistant general manager of KNPR-FM, 88.9, says that, right now, music licensing issues create an obstacle for local stations that might wish to offer podcasts of NPR programs.

KNPR's own locally produced programs -- Gwen Castaldi's "State of Nevada" news talk show, for instance -- might someday offer fodder for podcasts, Rogers says, but "we don't right now because it's a question of resources and also some technical things."

However, Rogers adds, podcasting and audio-on-demand are "really top-of-the-mind throughout the whole public broadcasting system."

"As soon as somebody can figure out a way for it to pay for itself or even generate some revenue in some way," Rogers says, "it's something that I'll think you'll see public broadcasters really dive into."

And when they do, it's likely that at least some of podcasting's pioneers will have moved on to whatever's next.

"I know there are a couple of Vegas-related podcasts that started up and died off after a couple of months," Dressen says. "I think the novelty wears off and people get tired and bored with it."

But, Dressen adds, "I'm having a blast."