Over the course of nine seasons, Seinfeld became one of the best sitcoms on television. The writing and unique sense of humor were some of the takeaways behind the greatness of a show about nothing. Nevertheless, the show has had a few recognizable guest stars who came across the soundstage at NBC.

The cameos that came out of this show really helped solidify some of these actors and give them their first big break. Needless to say, these names you'll come across are a pretty big deal.

Even at the height of the show, one of the stars from Friends did make an appearance on the show as Jerry's fake wife.

Jeremy Piven

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In 1993, Piven portrayed George Costanza on the show-within-a-show scene in the season four episode "The Pilot." From there on, the actor was a supporting cast member on the last three seasons on Ellen, playing the title character's cousin, Spence.

Piven would find success playing the no-nonsense Hollywood agent Ari Gold on HBO's Entourage. Recently, Piven had the main role as Jeffrey Tanner on the CBS drama Wisdom of the Crowd.