Best TV Guest Stars of All Time
There are some television shows that focus on celebrity appearances while others grace us with guest stars every so often. Whatever the case, we love when our must see TV shows decide to add our favorite celebrities in for some great cameos.

Here's our top picks of the best TV guest stars of all time:
10. Olivia Wilde, 'The OC'
Seth and Ryan had their share of celebrity run-ins during 'The OC' but Olivia Wilde's appearance as Alex, Marissa's lesbian partner, was the most talked about.
9. Hilary Duff, 'Gossip Girl'
While some might forget Duff's short stint on the Upper East Side as Olivia, dedicated fans will always remember the OMG moment she had with Dan and Vanessa that left everyone talking.
8. Lisa Kudrow, 'Scandal'
Talk about an epic return to television. As a rising politician, Lisa Kudrow joined Olivia Pope and Associates during the current season of 'Scandal'.
7. Nathan Lane, 'Modern Family'
When Cam and Mitch decide to plan their wedding, who better to help then Pepper Saltzman! Lane guest stars as the gay BFF everyone wants, except maybe when planning your wedding.
6. The Beach Boys, 'Full House'
It was a great day in the Tanner household when The Beach Boys appeared as themselves during the second season of 'Full House'. After being booked as guests of Wake Up San Francisco, obviously the group had to come sing along with the family in their living room.

With numerous special guests visiting the loft (can't wait for Prince!), Justin Long wins as Jess's boyfriend, Paul, in season one. Their quirky relationship and unforgettable sex scene goes down in 'New Girl' history.
4. Will Ferrell, 'The Office'
What's better than Will Ferrell and Steve Carell in the same episode of 'The Office'? Nothing! Audiences couldn't get enough of Ferrell when he played Deangelo Vickers for 4 amazing episodes.
3. Stevie Nicks, 'American Horror Story'
A Stevie Nicks cameo has been highly anticipated among the 'Coven' and audiences were not disappointed when it finally happened. As herself, a white witch, Nicks made such an impression that she is already confirmed to appear again- Yay!
2. Britney Spears, 'Glee'
There's nothing better than a Britney Spears 'Glee' tribute episode, especially when it features Britney herself! The princess of pop appeared through hallucinations the glee club kids were having while under anesthesia by their dentist, John Stamos. Talk about a star-studded episode.

Out of all the amazing guest stars to visit Central Perk, the best one, by far, is Brad Pitt. Back in 2001, Pitt appeared as Will Colbert, an old high school friend of Ross, Monica, and Rachel. What makes this cameo even better is that Brad and Jennifer Aniston were husband and wife at the time!
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