25 Actors You Forgot Were on 'Seinfeld'

Today marks the 25th anniversary of the greatest sitcom that was "about nothing."

"Seinfeld" launched 25 years ago on July 5, 1989 and still resonates in pop culture lore, with quotes and episodes talked about today, almost 16 years after the series finale.

Aside from launching the careers of Jerry Seinfeld, Jason Alexander and Julia Louis-Dreyfus, the iconic show also featured a slew of other stars well before their prime. In honor of the milestone, here are 25 actors and actresses that you probably forgot were on the show:

(And yes, we realize there are probably hundreds of guest stars, so we tried to pick a good 25!)

Kathy Griffin

The comedian played Sally Weaver.

Debra Messing

The "Will & Grace" star played Beth.

Kristin Davis

The "Sex & The City" star played a love interest of Jerry's.

James Spader

"The Blacklist" star played a childhood friend of Jerry and George's.

Jon Voight

Angelina Jolie's father played himself when George thought he bought his old car.

Amanda Peet

Peet played Linette, another love interest for Jerry.

Courteney Cox

The "Friends" star played Meryl, another girlfriend of Jerry's.

Jennifer Coolidge

Stifler's mom from "American Pie" played the masseuse, who Jerry wanted to get a massage from.

Jeremy Piven

The "Entourage" star auditioned to play George in his pilot for NBC.

Denise Richards

Richards played Molly, the daughter of the chairman of NBC.

Molly Shannon

The "Saturday Night Live" vet played Sam.

Lisa Edelstein

The "House" star played George's girlfriend.

Mariska Hargitay

She was the girl who had chemistry with Jerry while auditioning to play Elaine on his pilot.

Brad Garrett

He played Jerry's mechanic.

Marcia Cross

The "Melrose Place" star played a doctor yet again.

Lauren Graham

Graham played another love interest for Jerry.

Catherine Keener

Keener played another love interest for Jerry, you get the point.

Jon Favreau

The "Iron Man" star played Eric the Clown, who argues with George.

Michael Chiklis

"The Shield" star played a friend of the gang.

Bryan Cranston

Yep, even "Breaking Bad's" Cranston played Jerry's dentist.

Megan Mullally

She played one of George's girlfriends.

Teri Hatcher

"They're real and they are spectacular." You know who Hatcher played.

Debra Jo Rupp

"That 70's Show" star played Katie.

Anna Gunn

Another "Breaking Bad" star, she played Amy.

Marlee Matlin

The Oscar winner played Laura.