S/D artists whose entire known output is a single track on a compilation album

https://www.youtube.com/watch?v=uyaotTacLjw

Post mortem - Play

(most of the artists on this 1985 compilation don't seem to have released anything else, with the notable exception of the La's. I'd also recommend Fingerless gloves by Cassio Viletone, Bad night at Malibu Beach by the Happy Gauls and Terry Fields And A Pint Of Guinness by The Romulan Cloaking Device. Don't Cry Darling (Daddy Had To Drown The Cat) by Old Ma Cuxon And The Soapchoppers is good as well, but they put out a single.)

https://www.youtube.com/watch?v=HDtaaEtaItw

The Academy Of Fine Popular Music - The Morning After

Don't know if this strictly counts, but before forming Fairground Attraction, Eddi Reader and Mark Nevin recorded two tracks as the Academy Of Fine Popular Music which appeared on compilations put out by the Compact Organization.

https://www.youtube.com/watch?v=xlZv2cpLReM

Not exactly what you're talking about but this was a track on the East Coast Family Vol. 1 that featured the only recorded appearances of some of Michael Bivens' signees (like Whytgize)

Juicy Bananas! (Sy Richardson reciting his dialogue from Repo Man over a funk backing track.)

https://www.youtube.com/watch?v=dYwhINZgVeU

love mysterious idm/ambient/electronica tracks by one-and-doners

https://www.discogs.com/release/1697-Various-Aurora

who is melf?? who is Benjamin? gorgeous ambient nuggets

there's a ton of german examples of this. here's one that springs to mind - cosmic greatness

https://www.youtube.com/watch?v=DTiFS81Hfb8

This also doesn't quite count since the track was part of a 4 song EP (and that's all they ever released), but this was on a Clicks & Cuts comp and I was obsessed with it at the time

https://www.youtube.com/watch?v=wUXVXrdmuVM

band called Ellagaru had two tracks on a 1984 compilation A Secret Liverpool, no other releases

https://www.youtube.com/watch?v=-EAaLN_SG9A

https://www.youtube.com/watch?v=lt-ioDGTfms

do those ilm comps count?

The only one of these I can think of is "Talk Talk Talk Talk" by the Reaction (Mark Hollis's pre-Talk Talk band) that appeared on an indie compilation called Streets, but that still doesn't count because they also released a single called "I Can't Resist" before breaking up.

https://tomsmithksv.bandcamp.com/track/c01-silk-purse-nowhere-i-go

(2/3 of Sightings)

I wonder if a lot of those one-off ambient artists are better known people working under a pseudonym?

one of the album tracks on the first so so def bass all stars compilation (the one with "my boo" on it) is by an artist called t'baby (not to be confused with the legendary "it's so cold in the d" t-baby) who afaict never released anything else. all three of those compilations are uneven to a degree and yeah it's not exactly a "my boo"-tier classic but i always enjoyed it

https://www.youtube.com/watch?v=g1nfsl9BAzQ

the producer, danny d, and the guy doing the hype vocals, big ace, both have other releases, so idk if it totally fits but yeah

nah that totally fits, it's OK if the artists did other stuff (that Moet The Poet track I posted to start features members of Poison Girls and Ear Trumpet)

https://www.discogs.com/artist/329586-The-Organs-Of-Site & https://www.discogs.com/artist/329584-Richard-Steele

^^ love that record, excellent examples

Just guessing, but "Isgodaman" by Arthur Comics? (Streets)?

(The name of the band takes a question mark.)

ooh that's a good example of a pseudonym band! it was The Sniveling Shots but they were forced to use another name:
https://www.discogs.com/artist/536730-Arthur-Comix
https://www.discogs.com/artist/684538-The-Snivelling-Shits

lol sorry typos

I’m sure they at least had a b-side but I always loved The Hatfields “Yes I Do” from the first Back from the Crypt Cd comp.

here's one! probably multiple bands on this comp would qualify

https://www.discogs.com/artist/279363-The-Clones-2

https://www.youtube.com/watch?v=w0jl292aPJg

This cover of Green Day's When I Come Around was always a classic between me and my friends:

https://www.youtube.com/watch?v=gTsS1V0R6xQ

oh here's a good one

Bent Nails

Mike Luzader (drums), Byron Stamatatos (bass), Zach Georgopoulos (guitar) and Frank Portman (vocals)

Punk band from Millbrae, California that formed around 1979, while the band members were in High School. Frank and Byron would later go on to start The Mr. T Experience in Berkeley.

The only released Bent Nails track was "No More Riots" on the MRR "Not So Quiet On The Western Front" compilation.