The show was one of the biggest hits of the '90s, and anchored NBC's Thursday night lineup for a full decade, which meant they were able to land some pretty incredible names for all kinds of guest appearances -- whether it was up-and-coming stars or established A-listers.
"We had amazing guest stars," Schwimmer recalls in the new HBO Max reunion special. "Couldn't believe all these people, who we were massive fans of [were on our show]."
Some of the iconic guest appearances actually came from cast members' real-life love interests, like Cox's ex-husband, David Arquette, Perry's one-time girlfriend, Julia Roberts, and of course, Aniston's ex, Brad Pitt, who came on the show -- playing a former school friend of Ross', who hilariously hated Rachel with a passion -- the year after their highly publicized wedding in 2001.
"And your fella, Brad," Schwimmer teases Aniston in the special.
"Pitt came and did one," she replies, laughing it off.
This video is unavailable because we were unable to load a message from our sponsors.
If you are using ad-blocking software, please disable it and reload the page.
Brad Pitt and Jennifer Aniston Reunite for ‘Fast Times’ Virtual Table Read
Though they split over 15 years ago, Aniston and Pitt have made headlines with their friendly reunions in recent years, and a source told ET this week that the exes "respect each other and think each other is wildly talented and hilarious."
"[They] have been friends for quite some time," the source added of the former couple's present-day relationship. "There's nothing romantic there, but they are definitely aware that their fans are constantly rooting for them to get back together and laugh about it together."
In the Friends reunion special, the cast also recalls loving their episodes alongside Danny DeVito, who played a down-on-his-luck Strip-O-Gram gram in the season 10 episode "The One Where the Stripper Cries"; Ben Stiller, who gave the cast "one of our biggest laughs" as Rachel's rage-filled date in season 3's "The One With the Screamer"; and Schwimmer's acting idol, Sean Penn.
"And then we get the script and of course, I’m a potato," the actor recalls with a laugh, noting Penn's appearance in the season 8 episode "The One With the Halloween Party," where his character was dressed as "Spud-nik."
"I had very little, if any, dialogue with him," Schwimmer adds, "but here I am thinking, greatest actor in the world and I’m a f**king potato."
Friends: The Reunion is streaming now on HBO Max. See more of the show's epic guest stars in the gallery below!