From left to right, Michael Richards as Cosmo Kramer, Jerry Seinfeld as Jerry Seinfeld, Julia Louis-Dreyfus as Elaine Benes, Jason Alexander as George Costanza are seen in this undated image.
camera (NBC via Getty Images) From left to right, Michael Richards as Cosmo Kramer, Jerry Seinfeld as Jerry Seinfeld, Julia Louis-Dreyfus as Elaine Benes, Jason Alexander as George Costanza are seen in this undated image.

intro: 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!)

quicklist: 1 title: Kathy Griffin text: The comedian played Sally Weaver. media: 20486378

quicklist: 2 title: Debra Messing text: The "Will & Grace" star played Beth.

quicklist: 3 title: Kristin Davis text: The "Sex & The City" star played a love interest of Jerry's. media:

quicklist: 4 title: James Spader text: "The Blacklist" star played a childhood friend of Jerry and George's. media: 24418823

quicklist: 5 title: Jon Voight text: Angelina Jolie's father played himself when George thought he bought his old car. media: 24053801

quicklist: 6 title: Amanda Peet text: Peet played Linette, another love interest for Jerry. media:

quicklist: 7 title: Courteney Cox text: The "Friends" star played Meryl, another girlfriend of Jerry's. media: 24173511

quicklist: 8 title: Jennifer Coolidge text: Stifler's mom from "American Pie" played the masseuse, who Jerry wanted to get a massage from. media: 24418933

quicklist: 9 title: Jeremy Piven text: The "Entourage" star auditioned to play George in his pilot for NBC.

quicklist: 10 title: Denise Richards text: Richards played Molly, the daughter of the chairman of NBC. media:

quicklist: 11 title: Molly Shannon text: The "Saturday Night Live" vet played Sam. media:

quicklist: 12 title: Lisa Edelstein text: The "House" star played George's girlfriend. media: 24418775

quicklist: 13 title: Mariska Hargitay text: She was the girl who had chemistry with Jerry while auditioning to play Elaine on his pilot. media: 22858135

quicklist: 14 title: Brad Garrett text: He played Jerry's mechanic.

quicklist: 15 title: Marcia Cross text: The "Melrose Place" star played a doctor yet again. media: 24418723

quicklist: 16 title: Lauren Graham text: Graham played another love interest for Jerry. media: 24419040

quicklist: 17 title: Catherine Keener text: Keener played another love interest for Jerry, you get the point.

quicklist: 18 title: Jon Favreau text: The "Iron Man" star played Eric the Clown, who argues with George. media:

quicklist: 19 title: Michael Chiklis text: "The Shield" star played a friend of the gang. media: 24419115

quicklist: 20 title: Bryan Cranston text: Yep, even "Breaking Bad's" Cranston played Jerry's dentist. media:

quicklist: 21 title: Megan Mullally text: She played one of George's girlfriends. media: 24418639

quicklist: 22 title: Teri Hatcher text: "They're real and they are spectacular." You know who Hatcher played.

quicklist: 23 title: Debra Jo Rupp text: "That 70's Show" star played Katie. media: 24418886

quicklist: 24 title: Anna Gunn text: Another "Breaking Bad" star, she played Amy.

quicklist: 25 title: Marlee Matlin text: The Oscar winner played Laura. media: 24418591