Including the Star Trek fighting music from “Gamesters of Triskelion”?
Benny Hill used “Yakety Sax.”
Golden Girls used “Thank You For Being a Friend.”
One interesting case is Nadia’s Theme, which is known mostly as the theme music for the soap opera “the Young & the Restless.”
“Nadia’s Theme” was actually the theme music for the 1970/71 movie “Bless the Beasts and the Children” (and I think Karen Carpenter sang lyrics over the music.) It then got recycled sans lyrics as music for a promotional short about the gymnast Nadia Comaneci, and much to everyone’s surprise became immensely popular, even chartiing on Billboard.
Then it became the theme music for “the Young & the Restless”, which has been running ever since (while the Nadia Comaneci and the original movie have been mostly forgotten.)
“The Norm Show” used “Too Bad” by Doug & The Slugs.
This Old House used Fats Waller’s “Louisiana fairy tale”
And it’s a technicality but the theme from MASH was from the Movie and was, therefore, “existing” for the TV show.
Designing Women used “Georgia on My Mind”
Cybell used the Gershwin’s “Nice Work If You Can Get It.”
The Jack Benny Show used “Love in Bloom.” Bob Hope usually used “Thanks for the Memories” for his specials. Burns and Allen used “Love Nest.” In all cases they were song from their vaudeville days.
For years, the Huntley-Brinkley Report on NBC used the second movement of Beethoven’s Ninth Symphony. No royalties to the composer, and if they used the NBC Symphony version, they could probably use that for free, too.
The same is true of Star Trek: TMP and TNG.
“Those Were the Days” for All in the Family? :dubious:
“Alfred Hitchcock Presents” used “Funeral March for a Marionette”.
Season 2 of “The Leftovers” used “Let the Mystery Be” by Iris DeMent.
The Wonder Years - “With a Little Help From My Friends” Joe Cocker version. Or maybe it was the John Belushi version. I can’t tell the difference.
Nope, written for the show.
American Bandstand: Bandstand Boogie
The game show Definition: Soul Bossa Nova
This Week in Baseball: Gathering Crowds, from a little remembered show called Jackpot
John Prine typically states a “disclaimer” before performing Illegal Smile. I have seen him perform it at least 3 times and he has always had a bit of monolog before the song.
Prine explains that he wrote “Spanish Pipedream” when he started performing and that the album opener “Illegal Smile” was “not about smokin’ dope. It was more about how, ever since I was a child, I had this view of the world where I can find myself smiling at stuff nobody else was smiling at. But it was such a good anthem for dope smokers that I didn’t want to stop every time I played it and make a disclaimer.”
lSWYDT 
Wow. You nailed the first two songs/shows I thought of! I was actually re-watching Peep Show a couple of months ago and totally forgot they didn’t have “Flagpole Sitta” as the theme, but rather a more atmospheric intro with percussion sounds and a minimalistic little ploppy synth ditty over it.
Going into game show land–
“Now You See It” (1974-75 and 1989) used Quincy Jones’ “Chump Change”, a composition first heard on “The New Bill Cosby Show” in 1972-73 and then issued on Jones’ album You’ve Got It Bad Girl.
“A Swingin’ Safari” was composed by Bert Kaempfert and released on an album in 1962. It was used as the theme for the original “Match Game” for most of its run.
“The Savers”, originally released on the 1967 album Kaleidoscopic Vibrations: Electronic Pop Music From Way Out by Perrey and Kinglsey, was used as the “Joker’s Wild” theme from 1972-74.
“The William Tell Overture” for The Lone Ranger.
Weeds used “Little Boxes” by Malvina Reynolds. The first season used the 1962 original; seasons 2-3 used a new cover version each week, ranging from Elvis Costello to Linkin Park.
“journey of the sorcerer” by The Eagles is forever linked to “The Hitchhikers Guide to the Galaxy” (Radio, TV and Movie I believe)