Even if your computer is plugged into the wall using some kind of magnetic (dis)connector, there is stiil that nagging doubt that someone will fail to see the cable and manage to trip the whole thing (or themselves) to oblivion.
Today’s invention is to supply many valuable electrical items with a power cord which consists of, or carries, a section of light rope -the kind of stuff used in discos and naff shop displays the instant anyone mentions Christmas (ie from late July).
This would allow passing foot traffic to see a moving pattern of lights ‘pointing at’ the computer/ hi-fi /TV in question and thus to increase their chances of avoiding it. You might be able to choose to have the pattern change according to the current activity of the machine in question.
Now that these strings of lights are available in a ribbon-like form, it might make sense to use that, lying flat on the ground, in order to further minimise the trip hazard.