Many guest stars were not famous when they appeared on the show, but they are very famous now.  Below is a list of some of these stars.  (These are just the people I think are famous, add some more!)

Name Episodes
Mason Adams Paper Lion
Christina Applegate Band on the Run
Hank Azaria Designing Woman
Daniel Baldwin Basic Training
Stephen Baldwin Beyond Therapy
Christine Belford Art Lover
Alan Blumenfeld

Lady Sings the Blues

Auntie Up

Mr. Right

Beauty and the Bank

A Tale of Two Cities

Miracle in Columbus

Timothy Busfield

Little Man on Campus

Best Man

My Back Pages

Jeff Cohen

4 Rms Ocn Vu

The Visit

Geena Davis

Help Wanted

Karen II, Alex 0

A Word to the Wise

David Faustino To Snatch a Keith
Corey Feldman The Disciple
Jami Gertz Double Date
Crispin Glover

Birthday Boy

A Word to the Wise

Joseph Gordon-Levitt

Sign of the Times

Father, Can You Spare a Dime?

Tom Hanks

The Fugitive

Say Uncle

Noah Hathaway Designated Hitter
Dan Hedaya

Father, Can You Spare a Dime?

'Til Her Daddy Takes the T-Bird Away

Robert Klein The Boys Next Door
Charles Levin A Christmas Story
Judith Light Not an Affair to Remember
Julia Louis-Dreyfus Read It and Weep (Part II)
Constance McCashin Spring Reminds Me
Joshua John Miller Go Tigers
Penelope Ann Miller Higher Love
Priscilla Morrill

No Nukes is Good Nukes

M is for the Many Things

Tracy Nelson Ladies' Man
Danny Nucci Designated Hitter
Stuart Pankin The Visit
Rain-bow Phoenix Band on the Run
River Phoenix My Tutor
Martha Plimpton You've Got a Friend
Luis Daniel Ponce (Danny Ponce) The Real Thing
Anne Ramsey Help Wanted
Jack Riley Have Gun Will Unravel
Dick Sargent No Nukes is Good Nukes
Peter Scolari Once in Love with Elyse
Anne Seymour Remembrances of Things Past
Liz Sheridan Heartstrings (Part III)
Jay Thomas Super Mom
Marsha Warfield Keaton and Son
Wil Wheaton D is for Date
Daphne Zuniga Double Date
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