An example of a popular pirate (unlicensed) radio station in the U.S. today is Boulder, Colorado's "KBFR".
KBFR (Boulder Free Radio) broadcasts on 95.3 FM from a nondescript van that moves from place to place within Boulder. Sometimes KBFR transmits from a fixed location using antennas placed around town (hosted by local Boulder residents) and other times transmits directly from the van itself. KBFR also streams their signal live on the internet using wireless internet connections provided by dozens of Boulder citizens.
KBFR is run by a group of about two dozen private citizens called the Boulder Underground Radio Group (BURG). This group is made up of a broad range of people in their late teens to people well into their 50's. The people themselves include those that are well off, middle class and unemployed as well as professionals, businesspeople and students. KBFR's political viewpoints run from the far left to the far right with many in-between.
KBFR's goal is to create diversity on the airwaves and to bring a service that used to belong to the people, the radio spectrum, back to the community.
The government agency which regulates the airwaves (the FCC) has a charter to "protect the public interest". Instead, the FCC has auctioned off virtually all radio station licenses to the highest corporate bidder.
KBFR is a platform for new voices and new music. Listen to KBFR and you will hear new local musicians and uncensored alternative points of view not heard on any of your local "McRadio" (your typical Clear Channel Corp. owned station) or other mainstream media outlet.
KBFR is part of a new national underground radio network called the Real Public Radio network. The mission of the RPR is to counter the standardized radio that's emerging from the corporate media consolidation being engineered by the FCC today.
For more information, do a Google search on "KBFR".