Thiessen played all-American cheerleader (with the spectacularly 90's hairsprayed bangs to match) Kelly Kapowski on "Saved by the Bell" and the villainous Walsh cousin Valerie on "Beverly Hills 90210."
Keanu Reeves The...Known for both his good looks and his consistent (some say consistently wooden) acting style, Reeves played a range of roles from "Bill & Ted's Excellent Adventure" to "My Own Private Idaho." But perhaps his best work in the 90's was in the finest - and the only - surfer/bank robber film ever: "Point Break." Pictured here with co-star Patrick Swayze.
Keanu Reeves NowKeanu moved on to major stardom with his role as Neo in the futuristic "The Matrix" films, where his robotic delivery was a perfect fit for the character. (Photo by Mike Flokis/Getty Images)
Meg Ryan ThenThe bubbly queen of romantic comedies was as cute as a button in 90's hits like "When Harry Met Sally," "Sleepless in Seattle" and "You've Got Mail."
Meg Ryan NowMeg is still perky and blonde, but instead of looking older, she just looks... puffier. (Photo by Bryan Bedder/Getty Images)
Tom Hanks ThenMeg Ryan's cohort in romantic comedies made the leap into dramatic roles in the 90's, starring as an AIDS-afflicted gay man in the film "Philadelphia," for which he won an Academy Award. (AP Photo/Reed Saxon)
Tom Hanks NowLike Jimmy Stewart, Tom Hanks has maintained his status as one of America's favorite leading men due to his 'everyman' qualities. (AP Photo/Riccardo De Luca)
Julia Roberts Th...She played a hooker with a heart of gold and a thousand-watt smile opposite Richard Gere in the smash hit "Pretty Woman."
Julia Roberts No...Julia Roberts went from "Pretty Woman" to one of the highest-paid actresses of all time. (Photo by Andrew H. Walker/Getty Images)
Johnny Depp ThenDreamboat Johnny Depp started as a TV heartthrob on "21 Jump Street" and become a major movie star in the 90's with quirky films like "Edward Scissorhands" and "What's Eating Gilbert Grape." (AP Photo/Damian Dovarganes)
Johnny Depp NowDepp is still taking on eccentric roles, from the Keith Richards-inspired Captain Jack Sparrow in the "Pirates of the Caribbean" franchise to Willy Wonka in "Charlie and the Chocolate Factory." (Photo by Frazer Harrison/Getty Images)
Gwyneth Paltrow ...Gwyneth was a Hollywood darling of the 90's for her work in Anglophile films like "Emma" and "Shakespeare in Love." She was also briefly engaged to Brad Pitt (pictured). (GETTY)
Gwyneth Paltrow ...Paltrow's film career has quieted down during her marriage to Coldplay singer Chris Martin and the birth of her two children. (Photo by Pascal Le Segretain/Getty Images)
Alicia Silversto...She was the seminal 90's video babe, starring in three Aerosmith videos before her big roles as Cher Horowitz in "Clueless" and as Batgirl in "Batman and Robin."
Alicia Silversto...Silverstone's silver screen star has waned a bit in the 2000's. She's easier to find on TV or speaking out for vegetarian causes these days than in films. (Frederick M. Brown/ Getty)
Jennifer Aniston...The Rachel. It wasn't just a haircut, it was a moment in time, the defining 'do of an era. Just like grunge, The Rachel (and the show "Friends," where Jennifer Aniston portrayed the character of Rachel Green) will always be associated with the 1990s. (photo by NBC Television/Getty Images)
Jennifer Aniston...Aniston's left The Rachel - and TV - behind, starring in several successful films in the 2000's. She also starred alongside Brangelina in the biggest celebrity romance-breakup triangle of the decade. (Photo by Charley Gallay/Getty Images)
Claire Danes The...Danes channeled upper-middle class suburban teen angst in the short-lived TV show "My So-Called Life." Then she channeled Elizabethan teen angst in "Romeo + Juliet" opposite Leonardo DiCaprio. (AP Photo/Susan Sterner)
Claire Danes NowDanes is still performing in (mostly indie) movies, but is most notorious for allegedly breaking up the relationship of Billy Crudup and Mary Louise Parker. (Photo by Andrew H. Walker/Getty Images)
Mario Lopez ThenMario Lopez thrilled the tween set as A.C. Slater, resident wrestling jock on "Saved by the Bell."
Mario Lopez NowLopez is still thrilling the ladies - he was named People magazine's Hottest Bachelor of 2008. (AP Photo/Isaac Brekken)
Mark-Paul Gossel...As the preppy Zack on "Saved by the Bell," Gosselaar was always getting into trouble... and getting the girl.
Mark-Paul Gossel...After the "Saved by the Bell" franchise ran out, Gosselaar starred on 'NYPD Blue'. (AP Photo/Richard Drew)
Tiffani-Amber Th...Thiessen played all-American cheerleader (with the spectacularly 90's hairsprayed bangs to match) Kelly Kapowski on "Saved by the Bell" and the villainous Walsh cousin Valerie on "Beverly Hills 90210."
Tiffani Thiessen...She dropped the hyphen and the Amber and has quietly kept on working in TV. (Photo by Marsalli McGrath/Getty Images)
Luke Perry ThenWas there anyone sexier than the world's oldest teenager, Luke Perry, playing brooding high school sophomore Dylan McKay on "Beverly Hills 90210"? Not in the 90's!
Luke Perry NowLuke Perry never surpassed the success he had on "90210," but is still making television appearances. (AP Photo/Branimir Kvartuc)
Jennie Garth The...As Kelly Taylor on "Beverly Hills 90210," Jennie Garth played the most popular girl at West Beverly. As the show progressed, Kelly met with all sorts of drama: cocaine addiction, date-rape, amnesia, a fire and rehab.
Jennie Garth NowGarth is reprising her role as Kelly Taylor on the "Beverly Hills 90210" spinoff show. Kelly has now become a guidance counselor at West Beverly. (AP Photo/Peter Kramer)
Calista Flockhar...Unisex bathrooms, dancing babies and super-skinny starlets were all the rage on the groundbreaking dramedy "Ally McBeal," starring Calista Flockhart. (AP Photo/ Reed Saxon)
Calista Flockhar...Flockhart now stars on the show "Brothers and Sisters" and dates Harrison Ford. (AP Photo/Dan Steinberg)
David Duchovny T...Science fiction hottie David Duchovny steamed up "The X-Files" as Agent Fox Mulder. (AP Photo/Wyatt Counts)
David Duchovny N...Duchovny reprised his role as Mulder in the 2008 film "The X-Files: I Want To Believe." (Photo by Frederick M. Brown/Getty Images)
Matthew Fox ThenFox brooded as Charlie Salinger, oldest brother and caretaker of his parentless siblings on "Party of Five."
Matthew Fox NowFox now broods as Jack Shepherd on the hit ABC show "Lost." (AP Photo/Jae C. Hong)
Andrew Shue ThenAs the sweet, hapless Billy Campbell on primetime soap opera "Melrose Place," Shue was always being fought over by the ferocious female characters on the show.
Andrew Shue NowShue has mostly stayed out of the limelight, concentrating on raising his family. (AP Photo/Frank Franklin II)
Brainy BabesThese celebrities aren't just beautiful. They're brainy!
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