I think pink morning cartoon used to be reverse lost media. It started off as a strange YouTube video and then a group of people found out it was a show.
“I’m not gay, but I wish I was just to piss off homophobes” -Kurt Cobain
Now I'm not sure if this would count considering the song is now lost but there is this song I've been searching for called "Une Femme Comme Moi" and it's like a French song with a mix of jazz and blues posted by a group called LACN which from what I can see really only repost songs by other artists.
At the time when the song was up I couldn't find any information about it other than this odd document which when translated stated that the song came from this really old (like a century at least) French play so it must've been a modern take on the old song.
I really want to find this song again because it sounded so good, I remember it enough to at least try my best to sing some of the lyrics when I don't speak a lick of French.