By extra, I'm talking about songs by an artist that don't belong to an album. Songs from CD samplers, unreleased, etc..
I use a tag called TYPE. It can take values like EP, Single, Album, Compilation, etc. You get it. Everything that doesn't have that tag (or the tag is empty) is a single track, not part of any release.
I have great difficulties tagging unreleased songs too.
I have several CD singles in my collection. Mostly I'll just put brackets on the end of the title. Example: "Song Name [Radio Edit]". I put the album as what ever is on the cover. If there is no information, I put it as the song title with [Single] on the end.
That TYPE tag could be really useful, but so far, I've never had the urge to pragmatically create a playlist of all my singles.
I'm sure there are quite a lot of people with electromagnetic hypersensitivity that would buy these (the kind of people that sleep with the WiFi off or worse). And as long as there is demand, there's money to be made by fulfilling that demand.
Too bad the article on electromagnetic hypersensitivity is listed under <Alternative and pseudo‑medicine> on Wikipedia...
PS: These earphones would probably be one of the biggest violations of TOS #8.
I don't. I don't do unreleased tracks. It is either a proper album or single or extended play or compilation album. I check all my music on discogs. Official releases only. I check the "outtakes" on YouTube or Spotify if I get the urge to listen to the song.
Oh, yeah—those! I will come across some tracks that have not been released on any album. Often, they exist as a music video, only. Once converted to an audio format, I save these with the artist's other works, as if it were its own album with only one song (or, multiple songs, as is often the case with assorted concert footage). Folders begin with [year] of release, followed by the title of the song, or the place and date of the concert. Track names are always [artist] - [title]. Metadata will feature screenshots from a music video or other performance footage. Basically, treat it like an album, put it in a proper folder, and avoid "loose" tracks littering up your digital collection.
Original worthless reply:
Every genre folder (or, almost every one—certainly the larger ones) has a subfolder called "VARIOUS ARTISTS." And, yes, I use CAPS to make this one folder stand out.
Compilations go into the VARIOUS ARTISTS folders, listed by album title. While every other album is listed first by release year, I do not do that for compilations; I found doing so leads to frustration, later.
Most compilations are focused enough that everything clearly belongs to a given genre; however, there those those wide-ranging compilations with songs from myriad genres. In those cases, I select the genre most of the songs belong to, or the genre to which the most popular tracks belong.
I avoid loose tracks like the plague. They muddy the works. I buy albums. I do not pirate music, having been around long enough to witness the devastating effect on the music industry. FFS, why pirate, when you can get $2 albums from your local Goodwill?
This system seems to work well for me and my family.