Back in the early 1990s the Michigan Milita had a radio program. They started by reading coded messages, nonsense, designed allegedly for other "cells". These were the same kind on nonsense the British broadcast to the French Resistance during WW2. The Michigan Militia just scared the ----t out of the US government and so after the OK City bombing, Clinton openly when after this organization and they all had to go underground.
I would like to see any radio program incorporate this tactic as a sideline.