Jon Hamm
The Mad Men star memorably lent his voice to that of a talking toilet Gene found in the woods in the season two episode "O.T.: The Outside Toilet." His work, however, went uncredited.
Tiffany Haddish
In the season nine episode "Roamin' Bob-day," the hilarious Girls Trip star voiced the character Patricia.
Paul Rudd
Ant-Man himself was responsible for the vocal stylings of equine-obsessed Tina's imaginary horse Jericho in the season six episode "The Horse Rider-er."
Molly Shannon
The SNL comedian has been heard in four episodes over the years, beginning with season four's Halloween episode "Fort Night," voicing Louise's psychotic classmate Millie.
Megan Mullally
Practically a series regular at this point, the Will & Grace star has voiced several characters across 20 episodes. However, it's Linda's eccentric sister Gayle who she's played the most, beginning with the season one episode "Art Crawl."
Wanda Sykes
In the season six episode "Sacred Couch," Sykes played local TV personality Sofa Queen, enlisted by Bob and the kids to help convince Linda to replace their old couch.
Bill Hader
The Barry star has guest-starred in eight episodes over the years as bank robber Mickey, beginning with season two's "Bob Day Afternoon."
Carly Simon
The iconic musician played herself in the season five premiere "Work Hard or Die Trying, Girl," in which the kids' school puts on a production of the hilariously adult (and fictional) "Working Girl: The Musical."
Amy Schumer
In the season seven premiere "Flu-ouise," which saw an ill Louise fall into a wild fever dream reminiscent of The Wizard of Oz, the comedian lent her voice to the character of Young Lady.
Adam Driver
The Oscar-nominated Star Wars star lent his voice to Art the Artist, responsible for stealing the top of the Belcher's Christmas tree in the eighth season's two-part holiday episode, "The Bleakening."