Steve Kehela is Intervenor in The Pez Dispenser (Season 3 - Episode 14).
The trumpet player appears in The Mom and Pop Store (Season 6 Episode 8).
Thomas Dekker is Son in The Stand-In (Season 5 Episode 16) and Bobby in The Wink (Season 7 Episode 4).
Tim Bagley is Evan Fane, the manager in Ross' clothes store in The Maestro (Season 7 Episode 3).
Tim De Zarn plays the illegal shower heads salesman in The Shower Head episode (Season 7 Episode 15).
Tim DeKay is Kevin the Bizarro Jerry in The Bizarro Jerry (Season 8 - Episode 3).
Timothy Omundson is Ricky Ross in The Cheever Letters (Season 4 Episode 8).
Toby Huss is Jack (The Wiz), the spokesman for Nobody Beats the Wiz, that chants
«Nobody beats me, because I'm the Wiz! I'm the Wiz!» in The Junk Mail (Season 9 Episode 5).
Todd Bosley is Joey Zanfino in The Wait Out (Season 7 Episode 23) and in The Foundation (Season 8 Episode 1).