It's a podcast — the most popular on the Net according to fans. Think of podcasts as audio blogs you can listen to on an Apple iPod or other portable digital music player.

A growing number of podcasters are recording programs with free software and Web services and uploading them to the Internet, where MP3 player fans download them and listen whenever they like.

It's programming by the people, for the people — without overhead, censors or pesky professional standards to live up to.

Podcasting's most distinctive quality lies in the capacity to time-shift the consumption of digital content. Users can grab and tote their favorite shows, then listen while commuting, exercising or doing chores. Think TiVo for radio.

Big tech and media companies haven't weighed in yet on podcasting, a disruptive technology that could change the way digital content is delivered across the Internet. But there is no ambivalence on the part of the technologists who've embraced it.

"This is peer-to-peer computing at an organic level unlike anything we've ever seen," says Jake Ludington, producer of "The Chris Pirillo Show," a podcast on tech topics.

Curry, the one-time MTV video jockey, and the open-source software community of volunteer programmers nudged podcasting into the limelight last summer with a program dubbed iPodder that automatically downloads podcasts to iPods.

"Before you know it, I had people creating their own podcasts, sending me clips, and it kind of grew from there," Curry says.

By the end of summer, several dozen podcasters had cropped up, and a Google search for "podcasting" turned up a few hundred hits. Six months later, one popular directory lists more than 3,300 podcasts, and a Google search turns up 687,000 hits.

The BBC, a few National Public Radio stations and a handful of independent radio stations have begun posting select broadcast programs as podcasts. The radio stations aim to hedge against the day when it becomes common for listeners to download podcasts while they sleep, then "pod in" when convenient the next day.

"In large urban areas, we're dealing with long commutes, so it's important to find other ways to reach our listeners," observes Phil Redo, vice president of station operations at WNYC in New York City, the largest NPR member station.

Podcasters anticipate that the overall podcasting audience will continue to swell as the tools to create and subscribe to podcasts become more user-friendly. For the moment, a patchwork of tools makes trial-and-error de rigueur.

"Someone needs to take the geek factor out of it before you can have a revolution," says Rob Greenlee, host of WebTalkRadio.com.

Apple, in particular, is in a prime position to make podcasting significantly easier — but probably won't. It has ignored requests from Curry to discuss the matter, and declined to comment for this story.