Less than a year old, podcasting - the delivery of an audio broadcast to a portable player, such as an iPod, - appears poised to go mainstream.

Once the exclusive province of talkative technologists, do-it-yourself musicians, and obsessed hobbyists, this broadcasting platform has been embraced lately by well known media organisations.

Following a trial using Melvyn Bragg's Radio 4 In Our Time series, the BBC has started podcasting Five Live's weekly sports quiz, Fighting Talk.

Virgin Radio, meanwhile, has also jumped on the podcast bandwagon, making highlights of its Pete and Geoff breakfast show available to download.

The Virgin Radio podcast provides a half hour of edited highlights of its four-hour breakfast show minus he music, news, weather, traffic and travel.

After downloading free software, users synchronise their iPod or MP3 player with their PC and walk away with the latest, saved broadcast package, which they can then savour on their daily commute.

Another way of thinking of thinking of a podcast is as a weblog that delivers sound files instead of text directly to your computer.

You subscribe to podcasts by using a free audio-friendly RSS aggregator application such as Doppler, IPodder, or Nimiq. Just as with RSS feeds for blogs, any podcast subscriptions you create will be updated automatically with the most recent podcast. Many of the aggregators will automatically put the podcasts on your IPod, as well, but you can also listen on your PC or manually put them on another portable audio player.

No matter how many media giants take up podcasting, though, it is to likely remain a good tool for nearly anyone with a microphone, a PC, and some opinions.

US-based Tim Bourquin, for example, beams EnduranceRadio.com, a podcast on extreme sports, to an audience of 15,000 dedicated athletes. "Programming like mine simply doesn't work on traditional radio," he says.