While we’re at it, whatever happened to the cast of I Love Lucy? Seems like none of them have done anything in 20 years or so! 
He hasn’t really done a whole lot since The Office ended.
He was also a child molester in Diff’rent Strokes.
Bosom Buddies:
Peter Scolari went on to Newhart and is now the dad on Girls.
Holland Taylor probably comes next, she’s been in a bunch of stuff, like The Truman Show, with Ed Harris, from Appolo 13.
Donna Dixon was in The Twilight Zone and married Dan Aykroyd, who was in Dragnet with Christopher Plummer.
Wendy Jo Sperber was in the Back to the Future movies, and Bachelor Party, with Adrian Zmed and Tawny Kitaen.
That’s pretty much it.
Um… I think you’re forgetting someone obvious…
… Telma Hopkins went on to a long string of television appearances, as a guest star and as a regular. Duh.
Come on man, you’re forgetting the most successful one of all! Telma Hopkins was a regular on Family Matters, The Hughleys, and Half & Half, and she’s on Are We There Yet? right now!
Welcome Back, Kotter:
Most: John Travolta
Least: everyone else, including the star, Gabe Kaplan
Newhart:
Least: Julia Duffy
Most: William Sanderson, who played Larry. He’s been a character actor in countless shows, including Deadwood.
Wanted: Dead or Alive
Most: Steve McQueen
Least: I don’t remember anybody else
The Larry Sanders Show:
Most: Jeremy Piven
Least: Jeanine Garafolo
One that hasn’t been brought up yet…
Head of the Class (starring Howard Hessman from WKRP).
I’m sure many of the cast would be vying for least successful (let’s say Robin Givens or Hessman, because why not?) but most successful would have to be Dan Schneider, the heavy-set actor that played Dennis (sat in the back of the room).
You probably don’t know his name and haven’t seen him in much, but as a writer/producer/creator he’s churned out hit after hit for the young-people set including: “All That,” “Kenan & Kel,” “The Amanda Show,” “Drake & Josh,” “Zoey 101,” and “iCarly” (and several other shows.) He also wrote the movies Good Burger and Big Fat Liar.
According to CelebrityNetWorth.com, he’s worth about $20Million.
Tim Reid’s had a moderately successful career. He’s been a regular on three TV series.
Happy Days:
Most: Ron Howard (also arguably the most successful from Andy Griffith)
Least: probably Anson Williams (Potsy)
Laverne and Shirley:
Most: Penny Marshall as a director or Michael McKean as an actor
Least: Cindy Williams in a tie with David Lander
Three’s Company:
Most: John Ritter, hands down
Least: Joyce DeWitt
All In The Family:
Most: Rob Reiner (O’Connor and Stapleton were already well known and successful)
Least: Sally Struthers
Dick Van Dyke Show:
Most: Mary Tyler Moore
Least: Larry Mathews
Whatever happened to that dorky guy with the black curly hair? Hanks something?
For a guy who’s been living with multiple sclerosis since 1984, I’d say he’s had a pretty good career.
I’m not sure I’d put her in at all, since she died at the age of 47.
Small Wonder
Best: Edie McClurg aka Bonnie Brinde, mother of the next door neighbor has a full resume since 1989.
Worst: Plenty of choices but out of the core cast, both Marla Pennington aka Joan Lawson (Vicki’s “mom”) and Jerry Supiran aka Jamie Lawson have Small Wonder as their last IMDB credit.
I’m giving the show credit as “popular” since it got four seasons.
“Welcome Back Kotter”
John Travolta - most
Ron Palilio - least
“Moonlighting”
Bruce Willis - most
Cybill Shepherd - not least but boy, look how Willis shot ahead.
“Charlie’s Angels”
Jacklyn Smith - most
Cheryl Ladd - least
“Combat”
Vic Morrow - most had he lived on
the rest - ___
“Soap”
Billy Crystal - most
Guillaume, Mulligan, Urich - runners up
(all else) - least
“The Love Boat”
Gavin Macleod - most
Lauren Tewes - least
I’ll admit the bar is set pretty low but how has Gavin MacLeod had the most successful career since The Love Boat? He’s had a handful of guest starring credits.
Allyce Beasley
Kate Jackson was in Scarecrow and Mrs King for four years. That trumps Jaclyn Smith I think.
I think David Boreanz with “Bones” has almost as much claim to that crown as Hannigan, though she arguably beats him by a hair.
Wait, Tim who? Wasn’t he on The Office?
You do remember that Leonardo Di Caprio AKA the star of the second most successful movie of all time was on that show?