Unintentional Period Piece: The first two-to-three movies are shaping up into this as The '90s and early 2000s are getting further and further away. Of particular note: the cars, old police radars, the presidency of Jacques Chirac, people paying things in francs (France has adopted the euro currency since) and Daniel's "Zinedine Zidane #10" soccer jersey (Zinedine Zidane was the then-biggest star in French soccer, especially after helping the French team win the FIFA World Cup in 1998).
What Could Have Been: Franck Gastambide wrote, directed and played in Taxi 5. He wanted Daniel (Samy Naceri), the badass taxi driver protagonist of the previous films, to appear in it with an important role to play in the climax. Luc Bessonrefused. Gastambide then asked Naceri about a short cameo. Naceri refused the cameo, stating "I was expecting a little more respect after 30 years in the movie business".
Adored by the Network: While Taxi was one of the "bottom 10" shows of the 1981-1982 television season, somehow NBC still saw a worthy product in it and Un-Cancelled the show after ABC dropped it. Unfortunately, it "fared" no better with viewers on its new network and NBC was forced to cancel it (neither Cheers nor Family Ties got better numbers, but were spared by their numerous Emmy nominations; both wound up running much longer than Taxi).
Nick @ Nite and later TV Land kept Taxi on reruns for around a decade, building a large new fandom for the show. It helped that the show had a rather shiny picture of NY, making it look like it wasn't made in The '70s.
The Cast Showoff: Kaufman was able to perform dead-on impersonations of both Judd Hirsch and Tony Danza at some point during the series' run, in addition to creating the Vic Ferrari persona.
Channel Hop: From ABC to NBC in its last season. Ironically, the show which beat it in the ratings during the third season on NBC, Diff'rent Strokes, moved to ABC during its eighth and final season.
The Character Died with Him: Victor Buono played Jim Ignatowski's father in one episode. When he died, they killed off the character as well.
Doing It for the Art: After ABC cancelled the show in 1982, HBO made a bid to pick it up. At the time no cable network had even aired a sitcom before (mostly because almost no one had cable back then), which would have made for a very daring (and risky) move. However, Paramount decided to have Taxi on either CBS or NBC, the latter of which ended up airing the show in its final season.
Enforced Method Acting: One episode called for Louie DePalma to whisper something to Elaine Nardo, and for her to respond by slapping him and saying "That's disgusting!". Danny DeVito whispered such sweet things to Marilu Henner during rehearsals that she was genuinely shocked when he started whispering not-so-nice things, and she blew several takes because of it (to DeVito's delight).
When Carol Kane joined the cast as Latka's girlfriend Simka, Andy Kaufman taught her their country's "language" by inviting her to dinner and refusing to speak English or let her do so.
In one episode, guest star and real-life boxer Carlos Palomino accidentally delivered a real left hook to Tony's face. You can see Palomino pull his hand towards his mouth in horror for a second on realizing what he did before getting back in character and turning around to exit.
Hostility on the Set: The cast despised it whenever Andy Kaufman played Tony Clifton on the show because Kaufman refused to break character and acted as boorishly as humanly possible to everyone. It got to the point where everyone banded together and threatened to revolt if Kaufman wasn't fired immediately. The producers managed to come up with a compromise where they called Tony Clifton into a cast meeting, fired him, and had security guards physically throw him off the lot. This ensured that Kaufman couldn't bring the Clifton persona back onto the show and satisfied the rest of the cast enough to keep on working with Kaufman.
Real-Life Relative: Louie's girlfriend Zena was potrayed by Danny DeVito's real-life wife Rhea Perlman.
Also, DeVito's own mother Julia appeared as Louie's mom in a few episodes.
Tony Danza's son Marc Anthony appeared in two episodes of the second season, appearing in one as the kid Tony wanted to adopt.
Averted with Christopher and writer David Lloyd, with both being unrelated. Ironically, David is the father of another (also unrelated) ChristopherLloyd.
Screwed by the Network: An unintentional example. To boost the show's ratings, ABC placed Taxi for its third season on Wednesday, opposite NBC's hit show, Diff'rent Strokes. To be short, ratings dipped considerably (but not to the extent of Soap, which, by competing with The Facts of Life, hit rock bottom and was swiftly canned).
Troubled Production: Andy Kaufman never took the show seriously and often made ludicrous demands, most notably his showing up to the set in-character as Tony Clifton and causing utter chaos. To a lesser extent, Jeff Conaway suffered from a heroin addiction that kept leaving him unable to work for long periods, until he was fired.
Un-Cancelled: The show was abruptly cancelled by ABC after its fourth season, but it was picked by NBC for another year before being cancelled for good.
The Season 1 episode "A Full House for Christmas" was supposed to guest star TonyClifton as Louie's brother, but Clifton's behavior on the set was so awful that he was fired; he wound up being escorted off of the Paramount lot.
Originally "Touchdown" by Bob James was going to be the title theme but the producers liked James' slower music for the episode "Angela" and chose it instead.