A new research project at MIT's Media Lab aims to turn every cell phone or PDA carrying member of the public into a podcaster, and every mobile device into a virtual podcasting studio.

The first reportedly working prototype was built on a Motorola A1000 cell phone, and is currently being tested in Spain as part of the Electronic Lens project.

A live demo of the new project, which has been dubbed "RadioActive," should be available soon.

According to Judith Donath, director of the Sociable Media Group at MIT, the inspiration arose out of a complaint from one of her students.

"She received [a lot of] phone calls from people who didn't really have anything to say, but were bored," Donath said. "They were walking or driving, so they took out their phone and called their friends looking for entertainment."

By and large, more people are turning to their mobile devices for entertainment, says Donath, but rather than call, and potentially annoy, a friend, it would be ideal to "conveniently drop into an [ongoing] discussion and drop out when you're done."

The RadioActive project, which Donath created with student Aaron Zinman, defines a large-scale asynchronous audio messaging system, or mobile audio forum. In this system, voice messages, which are short audio sound bytes, are exchanged between groups of users via mobile devices, like cell phones or PDAs, as a method of "discussion-on-demand."

The messages are then collected in threads similar to how a common Internet discussion forum, like discuss.pcmag.com or even Slashdot, organizes text posts. Each message contains a subject, body, and author, as well as other metadata, and can range the spectrum from quick blurbs to full-length podcasts.

Since it can be time consuming to listen to long threads of voice messages as compared to scanning text in a discussion forum, community moderation has been incorporated into the system. "If lots of people say [a message] is not interesting, it's important that it fade into the background," Donath explained.

Just like an email application or an RSS reader, RadioActive supplies its users with an inbox, which displays the first message of discussion threads that have been subscribed to or are contextually relevant.

For instance, location may be one factor the system takes into account when determining contextual relevance. In this scenario, threads relating to New York City restaurants may appear in the inbox as the user walks around Manhattan.

The user can then navigate through messages in an active manner, by using the graphical interface (GUI) with a keyboard or voice command, or in a passive manner, in the so-called "Radio" mode. In the GUI, visual cues are displayed that allow the user to quickly determine interest level, size, age, and whether or not the message has been heard.

The user can then play messages in a specific thread or jump between threads. In Radio mode, the system plays messages sequentially so that the user can concentrate on other tasks, like driving.