There is just something really amazing about being able to communicate directly between two points on the planet by bouncing EM waves off layers of the atmosphere. Like, imagine two people hundreds of miles apart are shining flashlights (or torches, if you prefer) at the distant sky, just above the horizon, and seeing the sky glow from each other’s beams signaling each other. At the right frequencies and with the right conditions, certain atmospheric layer boundaries become reflective, like the boundary between air and water, so imagine that distant sky looks a little glossy up there, like water’s surface reflecting your beam.
But then run that light source through a machine that does that flickering signal fast enough to encode your voice in the pattern of flickering that’s glowing in the sky over someone else’s horizon.
That’s pretty closely analogous to what amateur (“ham”) radio operators are doing when they play with the HF range of the radio spectrum. The electronics are less sophisticated than cell phones, but our usual gadgets rely on many other devices to relay info across the Internet (which is also amazing, in a different way). Ham radio, on the other hand, is like a fancy version of talking through two cans on a string, sometimes up to thousands of miles apart, but using fast flash lights instead of string and cans.
Dirt!
I was just recommended a product called “Milorganite”, which is a soil product out of Milwaukee. They apparently ship it all over the US. People in, say, Florida are buying soil from Wisconsin.