(FORTUNE Magazine) – ONE OF MY FIRST illicit thrills was staying up past bedtime and tuning the AM radio to a station broadcasting only at night from hundreds of miles away across the Mexican frontier, one that played daring music--unsanitized rock & roll and rhythm and blues--that was never heard on my local stations. Midnight border radio had dangerous and exotic deejays, like Wolfman Jack, while my local station had a clean-cut guy named Sandy who played Top 20 hits straight from the Battle of the Blands.

Now, decades later, border radio is back, only this time without borders. And thanks to digital recording technology, you don't have to stay up past midnight to listen to it. It's called podcasting--the word is mashed together from Apple's "iPod" digital music player and "broadcasting"--and it is simultaneously a rebellion against the blandness of commercial radio, a demonstration of time shifting for radio, just as TiVo allows time shifting for television, and a celebration of the Internet's power to let individuals offer their own voices to a global audience.

Do you want to hear the latest Japanese punk music selected by an expert in the field? How about acerbic political commentary by Harry Shearer, otherwise known as the voice of many of the characters on The Simpsons television show? Or, for something you'd definitely not hear on commercial radio, how about Owennai:io: The Good Word, a podcast for people who want to learn to speak Kanien'keha, the language of the Mohawk nation? There are dozens of podcasts discussing sex and sexuality too. Sensitive listeners should be aware that, at least until Congress can no longer resist its primal urge to regulate new communications technologies, podcasting remains free from restraints on words or topics. And for now at least, listening to podcasts is free.

Podcasting combines the best aspects of TiVo and blogging. Blogging--writing and publishing personal, regularly updated journals, or web logs, on the Internet's World Wide Web--was the first tangible demonstration of the individual's ability to reach a target audience more effectively than through a media conglomerate. Today there are an estimated six million to seven million bloggers worldwide. Podcasting, which is basically blogging with the added dimension of audio, is the next logical progression in grass-roots media, just as radio emerged from print, and television emerged from radio. There are an estimated 6,000 to 7,000 regular podcasters today, publishing audio programs on the Internet for fun and perhaps someday for fame and profit.

Now, 7,000 podcasters may seem insignificant compared with the millions of bloggers out there, but looked at another way, there are twice as many podcasters today as there are commercial radio stations in the U.S. And each podcast voice is unique, while hundreds of radio stations have the same owners, the same playlists, and the same robot deejays.

Public and commercial radio stations are also hopping on the podcasting fad wagon, allowing their listeners to hear favorite programs whenever and--if the audio files are transferred from the computer to an iPod or other MP3 player --wherever they like. (Despite the name, podcasting does not require an iPod; podcasts can be heard through any Internet-connected PC or transferred to any portable MP3 player.)

Finding and listening to podcasts just got a lot easier with the release of Apple's iTunes 4.9, a free download from apple.com. The new version of iTunes allows users of Windows or Mac OS X computers to search for podcasts by keyword, subscribe to them for automatic updates, and transfer them to an iPod for playback at the listener's place and time of convenience. Users can sample a given podcast and if it proves interesting, subscribe to it. Then every time the podcaster publishes a new program, the iTunes software will capture the audio file in a form that can be listened to through the PC or Mac or transferred through iTunes to an iPod for enjoyment during the morning commute or gym workout.

While Apple is leading the pack by incorporating podcast technology in its software, anyone with a web browser and "podcatching" software for gathering the latest podcasts can listen in on the new trend. My favorite Windows podcatching software, besides iTunes, is iPodder (ipoddernet.sourceforge.net) and its Macintosh counterpart, iPodder X, although dozens of other programs can be found through podcasting sites like Podcast Alley (podcastalley.com), which aspires to be to podcasting what Yahoo initially was to the Internet. Other places to search for interesting podcasts or podcatching software include iPodder, podcastingnews.com, and podscope.com.

But listening is only half the fun. If you have something to say or to share in an audio kind of way, why not create your own podcast and become a pod star?

Basically, anyone who has an Internet-connected computer, a microphone, some audio editing tools, and an understanding of the terms RSS, MP3, XML, and hosting--okay, so we lost some of you with that last part--can become a podcaster, or Internet radio deejay and talk-show host.

RSS (really simple syndication) is a technology for delivering automatic updates of information to subscribers. Many of the better websites and blogs offer RSS feeds, which deliver constantly updated headlines or articles automatically, instead of requiring the reader to go to each site for updates.

MP3 files are audio files compressed for more efficient delivery over the Internet. While podcasts are mostly MP3 files, some use other compression formats, like WAV or AAC. MP3 is popular because it does not include digital copy protection.

XML is a programming language, similar to the HTML language used to create web pages, that allows data to be shared across many different kinds of computers, typically over the Internet. RSS is based on XML.

You'll have to have a place to put your podcasts so that other people can download them, and that means having an Internet host. Ask your local Internet service provider about hosting, or, if the previous paragraphs leave you speechless, Audioblog.com offers a free seven-day trial of all the tools necessary to podcast, as well as podcatch. And if a week's worth of podcasting persuades you that you have what it takes to become a pod star--and frankly, the bar is set pretty low these days--a year's membership in audioblog.com is just $50 if paid at once, or $5 a month.

Then you'll want to invest in a set of noise-canceling headphones with microphone, like the Plantronics DSP-400 ($80). It plugs into the USB port on your PC or Mac. If you prefer a podcasting service other than audioblog.com, you'll need an audio-capturing and -editing program too. Apple's GarageBand is one alternative for the Macintosh set, but an interesting newcomer is MixCast (mixcastlive.com), a $40 program for Windows that provides all the tools for making a good podcast.

Podcasting won't kill radio, but it will definitely kill a few hours as you explore what the rest of the world has to say.

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