Throwing a fictional universe's characters together into one film (here's looking at you, The Avengers and Man of Steel: Superman Vs. Batman!) is a popular new trend in movies, but TV crossovers have been happening for decades. Here are 11 TV crossovers in animated and live-action television.

1. Jay Sherman (The Critic) on The Simpsons

In 1995, The Simpsons aired an episode called “A Star Is Burns,” which featured Jay Sherman from the then-new animated TV series The Critic. In the episode, Springfield puts on a film festival and calls Jay Sherman to be one of its jurors.

While both shows were on Fox, The Simpsons was more popular, and the network used its popularity to try to boost The Critic’s dwindling ratings. Simpsons creator Matt Groening was so upset with Fox and The Critic’s executive producer James L. Brooks—who is also an executive producer for The Simpsons—about the crossover that he took his name off the episode. While the crossover didn’t hurt The Simpsons’ reputation, The Critic didn’t find new viewers, so it was canceled a few months after the episode aired.

2. Steve Urkel (Family Matters) on Full House

In the early '90s, the television character Steve Urkel from ABC's Family Matters turned into a pop culture phenomenon—the character spawned a breakfast cereal, a pull-string doll, and other merchandise. Urkel also appeared on other television shows—including Step by Step, Meego (on CBS), and, most notably, Full House.

In a season four episode of Full House called "Stephanie Gets Framed," the Tanner household was turned upside-down when Urkel paid his cousin Julie a visit—and helped Stephanie deal with her unease about wearing new glasses.

3. Cosmo Kramer (Seinfeld) on Mad About You

In the first season of Mad About You, Paul and Jamie write a living will after they both become obsessed with death. Jamie learns that Paul still owns his old bachelor pad, which he has been subletting to Kramer from Seinfeld. Paul ends up giving his old apartment to Kramer and we figure out why Kramer never pays rent.

4. Belcher Family (Bob’s Burgers) on Archer

Although the characters Bob Belcher from Bob’s Burgers and Sterling Archer from Archer have very little in common—one is a hardworking family man, while the other is an sex-obsessed superspy—they are both voiced by actor H. Jon Benjamin.

Archer creator Adam Reed is a big fan of Bob’s Burgers, so when the season four premiere of Archer involved the titular character having amnesia, Reed saw the perfect opportunity to do a crossover. In the episode, Archer has the false identity “Bob” and is working at a hamburger restaurant with a new family. The Belcher family was drawn in the Archer style of animation, and H. Jon Benjamin gave Archer Bob Belcher's voice.

5. Abed (Community) on Cougar Town

One of Community character Abed’s favorite TV shows is the comedy Cougar Town. In season two of Community, Abed tells Jeff Winger that the producers of Cougar Town invited him on a set visit of their TV show. He accepts and in Cougar Town’s second season finale, you can see Abed in the background trying to act natural as a background extra.

6. Travis and Laurie (Cougar Town) on Community

During Community’s second season finale, Travis and Laurie can be seen celebrating when Greendale Community College wins the paintball competition with rival school City College.

7. Fresh Prince (The Fresh Prince of Bel-Air) on Blossom

In the season two Blossom episode “I’m with the Band," Blossom and Six go on a band trip and stay, unsupervised, in a hotel room. Six learns that the Fresh Prince is staying in the same hotel, so they both try to find him. They almost give up—and then, Blossom randomly meets the Fresh Prince in a hotel elevator. As proof of their meeting, the Fresh Prince gives Blossom his funky, fresh hat.

8. Ally McBeal Meets The Practice

Ally McBeal and The Practice were two David E. Kelly TV shows about lawyers from Boston that premiered in 1997. Ally McBeal was a comedy on Fox and The Practice was a drama on ABC.

The crossover, which happened on April 27, 1998, started with the Ally McBeal episode “The Inmates,” aired first. It featured an axe murder that proved to be too much for the law firm of Cage, Fish, and Associates to handle—so they asked for help from a more experienced group of lawyers, The Practice's Robert Donnell and Associates.

Immediately after Ally McBeal aired on Fox, the story continued on The Practice on ABC with the episode “Axe Murderer.” The crossover continued a few weeks later in Ally McBeal’s season finale episode, “These Days Are Gone.”

9. Caroline (Caroline In The City) on Friends

During the height of NBC’s Must-See TV Thursday night programming, the peacock network sometimes used gimmicks to generate more viewership for the weaker portions of the four TV sitcom block. In 1994, NBC introduced “Blackout Thursday,” where three of the four sitcoms experienced a citywide blackout. The following year, on November 2, 1995, NBC introduced “Star-Crossed Thursday,” where characters from each Must-See TV sitcom would appear in a different show.

In the episode, “The One with the Baby on the Bus,” Chandler and Joey are babysitting Ross’s newborn son Ben, while Caroline Duffy mistakes them for a gay couple when Chandler and Joey try to hit on her.

10. Ross (Friends) on The Single Guy

Also a part of Star-Crossed Thursday was The Single Guy episode “Neighbors,” in which Jonathan meets Janeane’s friend Ross at a dinner party. Jonathan and Ross hit it off and the pair later goes to the theater to watch Leonard Nimoy in Hamlet. Both think the other man is gay.

11. Chandler (Friends) on Caroline in the City

The final part of Star-Crossed Thursday was the episode “Caroline and the Folks." Chandler hits on Annie in a video store, as he tries to impress her with his knowledge of art-house films.

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Which other crossovers do you remember?