In the 100th episode, Jack explains to Tracy what will happen to his movie star reputation once he begins doing TV again...
In the West Coast broadcast of the Live Episode, someone suggests they cut out a sketch based on Capital One credit cards. Alec Baldwin turns to the camera and repeats his pitch from those same commercials.
Doubled with Hypocritical Humor: Jack mocks Jenna for wanting a producer's credit, claiming its a cheap handout to shut actors up. This just before "Producer: Alec Baldwin" ticks across the screen.
Guest star Matthew Broderick's episode featured him and Jack searching government files for the worst plan ever, which was guaranteed to offend everyone, flop, and get them both fired. The plot and Broderick's mannerisms are very similar to his role in The Producers.
After dating Matt Damon for half a season, Liz tries to remember who played the white guy in Invictus.
A minor, possibly unintentional example: Liz refers to her ex, Dennis, as "the Terminator with cheaper glasses." Dennis is played by Dean Winters, who played Charley Dixon on Terminator: The Sarah Connor Chronicles.
In the first episode of Season 4, Steve Buscemi, who plays a private investigator, claims that he is called "The Chameleon". In Monsters Inc., Steve Buscemi voices Randall the chameleon.
At one point in Season 1, Liz has an awkward interaction with Floyd, who's carrying a basketball. Floyd is played by Jason Sudeikis, who is a big amateur basketball player and had a shot of him shooting hoops as his introductory on the Saturday Night Live opening credits.
Tina Fey's real first name is Elizabeth ("Tina" coming from her middle name of Stamatina), of which "Liz" is a nickname.
Grizz is both the character's and actor's first name.
Sue LaRoche-Van der Hout is played by Sue Galloway.
Dawson Casting: Jenna seems to think she's up for an audition as a college freshman on Gossip Girl in "Black Light Attack!". She was actually up for that character's crazy bitch of a mother - who dies of old age at age 42.
Averted throughout as every actor is the same age as their character with Katrina Bowden possibly even younger than Cerie and every teenager played by an actual teen. Played straight in one instance with twenty-six year old Pheobe Strole as a teen.
Tina Fey appears as a younger Liz Lemon in a number of flashbacks. In one of them, she was nine.
Jason Sudeikis as Nice Guy Floyd, which is quite a contrast from the loudmouthed idiots, boisterous Southerners, and preppy douchebags he normally plays (both on and off Saturday Night Live).
In the show itself, Tracy Jordan was known to do this. In the movie, Black Cop/White Cop, Tracy played the white cop. According to Tracy, he was set to star in the movie Rush Hour until being replaced by Jackie Chan. He also starred in a movie with Betty White about a rapping grandma. Betty remarked about how well Tracy played the grandma. And there's a constant tension between his normal persona, his happy home life, and his efforts towards critical success.
Tracy played both the black cop and the white cop.
Throw It In: The Credits Gag of "Black Light Attack!" has Lutz dancing energetically, with the rest of the cast chanting, "Go Lutz! Go Lutz! Go Lutz!" It was actually completely unscripted, as the actor Lutz was grooving to the generic techno music. It was such a fun moment that the scene was left in.
Among aspects to have changed from the initial draft of the "Untitled Tina Fey Project" script (later to become the basis of the Pilot episode), Liz Lemon was named Lisa Lemon, Tracy Jordan (presumably not yet cast) was Lawrence Jordan, and the SNL-like show Jenna initially appears in is called "Friday Night Bits" (set to be retooled by Jack into an Artifact Title-free "The Lawrence Jordan Show").
Word of God: We know of Cerie's last name (Xerox) from executive producer Robert Carlock. We know of Liz and Jack's lack of a romantic future from Tina Fey.
Writer Revolt: When forced to write an environmental-themed episode for NBC's Green Week, the writers instead wrote a brutal satire of NBC's own environmental greenwashing, and then did it again the following year, and brought back former VPOTUS Al Gore to "re-cycle" a joke. Also the one episode broadcast during the WGA writer's strike in Season 2 (the unnamed Episode 210) has no writers in it, implying that they are on strike. During the Writer's Strike, the cast of 30 Rock performed a live episode on-stage off-Broadway to raise money for the strikers.