I'm aware of a handful of other radio stations that are powered by FLOSS but none are as free as Dark City. Not only is it powered by FLOSS (KXStudio, IDJC, Mumble, VNC, PHP etc) but its totally uncensored and anyone who has something interesting to say can get on the air or even have their own show if they're prepared to put in the time!
Dark City's use and promotion of free and open standards and software has stepped up a gear recently as people can now participate via Mumble in addition to Skype. Not many people are familiar with Mumble so I created the following vid under KXStudio to demonstrate the process of installing and configuring Mumble:
http://www.youtube.com/watch?v=_slsSlcUDcY
I just used the mic built-in to my laptop so the sound is nothing special but its good enuff for the job!
Dark City Radio Mumble Guide
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