With the ILLW (International Lighthouse and Lightship Weekend) coming in August, here's a map of all the lighthouses across the globe. Perhaps there's one near you!
An RTL dongle can be used to create a band survey showing radio interference over time. This chart shows time vs frequency vs intensity in two different formats.
Based on data from the 1996 Gazetteer of Australia I generated a KMZ file that shows their locations.