If commercials are in scope, then there’s a veritable gold mine of humorous allusions to be found in celebrity endorsements. Advertisements featuring Don Adams (and he did an awful lot of them, for a variety of companies) are chock full of references to his role in Get Smart.
To bring it back to OP’s request, George Lazenby made an allusion to his previous role when he made a cameo fourteen years after his solo Bond film in the 1983 TV movie Return of the Man from U.N.C.L.E. His short appearance as ‘JB’ driving an Aston Martin fitted with special gadgets to take out the bad guys on a car chase and a reference to On Her Majesty’s Secret Service right at the end.
Ray Milland shows up on the Love Boat playing another character’s father, who had struggled with alcoholism - a reference to Ray Milland’s famous role as an alcoholic writer in “The Lost Weekend”
Anna Massey was in “Happy Families”, an episode of “Inspector Morse”. Morse’s regular sergeant was Robbie Lewis.
She played a different role in “Whom the Gods Would Destroy” in the series “Inspector Lewis” (who was promoted after Morse died). She says to Lewis, “I’m sure we’ve met, haven’t we? Or in another life perhaps.”
Not a different role: in the series “Endeavour” (a prequel to “Inspector Morse”), the daughter of John Thaw (who played Morse) has a recurring role. Her first lines in that series are similar to Anna Massey’s lines in the Lewis episode.
I was watching The Jeffersons last night. The name of the episode was Mission: Incredible. It had Greg Morris, one of the actors in Mission: Impossible. The first time they showed him they played the music from Mission: Impossible.
I watched Charade yesterday with Cary Grant and Audrey Hepburn. Cary Grant said “on the street where you live”. My wife recognized this from My Fair Lady, staring Audrey Hepburn.
Then I looked it up and Charade came out the year before My Fair Lady. According to a website, Audrey Hepburn had just been cast as the lead of My Fair Lady.
So, this makes this a humorous allusion to an actor’s future role.
In the Black Mirror episode “White Christmas”, Jon Hamm is asking a character to guess his occupation from the life “before”, and the character guesses “I dunno, advertising?” (Hamm played an advertising executive in an earlier television show).
The original Wayne’s World features a cameo appearance from Robert Patrick, reprising his role as the T-1000 from T2: Judgement Day, and he’s still looking for Edward Furlong.
He’s also in the Arnold Schwarzeneggar movie The Last Action Hero, also pretty obviously playing the T-1000
‘NCIS’ Episode ‘Being Bad’ has John Kapelos (Carl, the janitor, from “The Breakfast Club”) making a reference to the decedent having caused a ‘ruckus’ in high school.
In Return of the Living Dead 2 (a movie so awful that it has a “zero” rating on Rotten Tomatoes, although it did more than earn back its expenses ) James Karen and Thomas Mathews, who were in the first Return of the Living Dead movie, play essentially the same characters (with even the same dialogue). at one point Mathews’ character says
Season 9 of “Stargate SG-1” Ben Browder joins the cast. In the first episode his former costar from “Farscape” Claudia Black, who appeared in one episode a couple years earlier, comes through the stargate, looks at him and says I haven’t met you before.
The last appearance of William Frawley was on “The Lucy Show” where Lucille Ball meets him, walks away saying he looks very familiar.
Ian Hendry co starred with Patrick MacNee on the first season of the “Avengers” (only a few episodes survive). 17 years later he guest starred on “The New Avengers” with MacNee saying don’t wait 17 years to get in touch again.
I caught the end of the movie, Valentines Day, (which was running continously on one of the cable channels. During the credits, they showed outtakes. Julia Roberts, who plays a returning soldier being chauffeured home, is asked by the driver: “We’re passing by Rodeo Drive, have you ever shopped there?”
Her reply" “only once. Big mistake. Big. Huge.”
Just found this one: William Frawley’s last TV appearance. The reference comes at the end of the clip.
I didn’t read through the whole thread, but in Hot Shots: Part Deux, there’s a scene in which Charlie Sheen is traveling upriver in a boat, and his father Martin Sheen is in a boat traveling downriver. As they pass, both Sheens shout out, “I loved you in Wall Street!” Charlie co-starred in that movie, and the elder Sheen had a supporting role as his father. It’s also a humorous tribute to Martin Sheen’s role in Apolypse Now.
Maybe mentioned before, but Martin played Charlie’s father on his show Anger Management. There are several references to both their past performances. The last one I saw Charlie was saying something like “I could never imagine you as the president”.
On Young Sheldon, Sheldon’s sister Missy mentions the show Blossom, and Sheldon says “Never heard of it.” Missy says “She wears these hats.” Sheldon looks completely blank.
The subject comes up, because Missy says that Joey would be a good boyfriend for one of her dolls.