ZipperJJ helped me remember one that popped up not too long ago: Art Blakey- Ocalypso (some other group doing it) is now being used in some cruise line commercial. Although it hadn’t really dropped all the way out of my mind it took a while for me to identify the tune. It was on one the first LP’s I ever owned back in the late 50’s. I used to try to play my bongos along with it and the other tunes on the album.
I think I already mentioned this in another thread.
“…I thought I knew you so well …”
You mentioned that song and the line instantly popped into my head. And it may be over 20 years since I’ve thought of it, too.
OUR DAY WILL COME - Ruby and the Romantics
The Box Tops - Sweet Cream Ladies , Forward March
James Vincent - Space Traveler
Batdorf and Rodney - “All I Need” - too obscure for YouTube!
I think “Feeling Stronger Every Day” and
Jefferson Starship’s “Miracles”
best epitomize’s 70’s AM radio.
Somewhere between the ages of 11 and 33, I completely forgot about Roxette’s “Joyride.” It was randomly playing one day when I picking up lunch at a deli.
Not sure if that is a subtle dig/whoosh, or what, but I’ll just mention that that song just shuffled on my computer player, out of 500 song list (I usually play stuff on random shuffle)…
The one they are using on the car commercial these days: “I guess you wonder where I been…” (Got a thing for you and I can’t let go) takes me right back to being a kid playing in our street. I must not have heard it very much in between since its memories haven’t been replaced.
I was in a Rescue Mission thrift store today and they were playing the BEST music from the 80s, the very best songs of the 80’s. I heard:
“Tall Cool One” by Robert Plant
“Family Man” by Hall & Oates
“Something Always Breaking Us in Two” by Joe Jackson
Three of my favorite performers, and three nearly forgotten songs. It was great! 
Find the River by REM was just rediscovered by me about a year ago.
I love that song. Maybe a bit too strong on that 70s-era sweetening, but it’s really a lovely work and Syreeta’s voice is unparalleled.
Here is one I heard, once, in a restaurant in Ohio back in the 90’s. Even then I had forgotten this song, and have never heard it since:
Pilot of the Airwaves, by Charlie Dore.
How’s about one hit wonder Bourgeois Tag’s “I Don’t Mind at All”?
Valley of the Kings - Tangerine Dream
My Mother, the War - 10,000 Maniacs
Misguided Angel - Cowboy Junkies
Teenage Nervous Breakdown - Little Feat
Guess you could say I had exotic tastes.
I hate you for reminding me that that Automatic for the People was 20 years ago! 
There was a late night radio show back in the mid-60s when I was a teen that played a lot of R&B; sort of like Venus Flytrap. It had an instrumental theme song that I was instantly wild about, but they never said the name or artist. I listened for weeks until finally the DJ announced: "As always, that was. . .
Soul Serenade, by King Curtis"
I raced downtown the next day and ordered the 45 record, and I played it till the grooves wore out and I had every note memorized. Then I forgot about it as life took over and rediscovered it some 30 years later. I still love it.
I hadn’t heard “I Do the Rock” by Tim Curry in 30 years or so, then heard a reference to it a few weeks ago.
And Rockne’s very K-nute I know!
Fun song.
I’m reminded of the episode of Friends where Ross shipped Marcel off to a zoo. As they were waving goodbye to Marcel, John Sebastian’s “You’re A Big Boy Now”, his solo studio version came up. That took me back.
I had the same experience here in Chicago with the late night DJ known as “Mister A”. He would end every show with that tune but never mentioned what the name of it was. I finally found out it was Soul Serenade by Oliver Sain. You got to check out this version. It will make the hair on the back of your neck stand up.
A more “jazzy” version, for sure. The guy had incredible breath control, and nailed the piece. Curtis was appealing to the pop/soul audience, I think, so his version was more vamped. I was surprised to see that The Allman Brothers covered the song.