Hrrm. Maybe up to 25 years ago, but certainly 30 years ago you had similar phenomena via FM-Radio. Depending on what you did, there were different interferences

Hrrm. Maybe up to 25 years ago, but certainly 30 years ago you had similar phenomena via FM-Radio. Depending on what you did, there were different interferences in the radio. Unzipping something made different sounds than compiling, running a raytracer, or zooming into fractals. One could use that while half asleep in the bedroom, whith a radio tuned into the right frequency, almost muted, and then know if Portage on Gentoo, or build.sh/pkgsrc on NetBSD was ready, or interrupted. Because no buzzing or humming anymore :-)