We don't get why Levi Johnston is famous. Seriously. Someone needs to explain this one to us. He got a Vice-Presidential candidate's teenage daughter pregnant and has subsequently gone on an obviously revenge-fueled media blitz. And it's all culminating with his seminude photo shoot for Playgirl magazine. Then, hopefully, Levi will go away (unless Kathy Griffin decides to keep using the boy-toy for her own publicity stunts).

Playgirl seems like the perfect career move for someone whose 15 minutes of fame are almost up. But Johnston isn't the first celebrity to take off his Levis for the adult magazine. Since the erotic publication debuted in the early '70s, there have been  others who thought baring all — or mostly all — was a good idea. You might be surprised by some of the celebs who disrobed for Playgirl over the years. In retrospect, we wonder if Keith Urban thinks all of the exposure was worth it.

Photo gallery: See the celebrities who've appeared in Playgirl through the years.

Brad Pitt – August 1997

Let's be very clear about one thing: Brad Pitt DID NOT pose for Playgirl. In fact, the megastar sued the magazine when it published ten revealing photos of Brad in their August 1997 issue. According to Pitt, the pics had been snapped by a trespassing paparazzo while he was on a 1995 romantic getaway in the French West Indies with then-girlfriend Gwyneth Paltrow. A judge ordered Playgirl to stop shipping issues of the magazine but allowed them to keep the copies that were already in circulation on the stands. Pitt wasn't the only celeb to sue the magazine. Leonardo DiCaprio prevented the publisher from running photos of him in 1998, and Antonio Banderas threatened legal action after Playgirl ran shots of the Spanish star au natural, photos that he claimed were digitally fabricated and not him at all.

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Christopher Atkins - September 1982

Fans of Christopher Atkins had already seen their heartthrob naked in his feature debut, "The Blue Lagoon." Still, they must have been thrilled when he agreed to appear in Playgirl — not once but twice. Chris was on the cover of the September 1983 issue, which featured a nude pictorial of the blond cutie. And he reappeared a couple of months later in the December issue. That was pretty much the last public exposure of any kind that Atkins would have for a long time. While the actor continued to work consistently, he faded from the spotlight until reemerging last year on the VH1 reality show "Confessions of a Teen Idol." Now he has six feature films due out in the next year.

Lyle Waggoner - June 1973

Younger pop culture fans may not know who Lyle Waggoner is, and even '70s TV fans might not be able to put a face with the name. From 1967 to 1974, he costarred on "The Carol Burnett Show," but he was never the most memorable performer; he did, after all, have to share the spotlight with the comedic genius of Burnett and Harvey Korman. Maybe that's why Lyle wanted to draw a little attention to himself by appearing as the first celebrity centerfold in Playgirl magazine's premiere issue. But in a four-page spread in the June 1973 publication, the mag's Man of the Month bared (almost all) while sitting cross-legged at a roll-top desk.

The following year, Waggoner left the "Burnett Show" behind (he was replaced by the legendary funny man Tim Conway), and took the part of Steve Trevor on the very family friendly series "Wonder Woman." We're guessing most parents didn't know about his prior work.

Keith Urban – April 2001

Lots of fans picked up the Playgirl issue that teased: "Legend has it, Keith Urban is country music's BIGGEST new star!" Unfortunately, curious fans will never know  the truth behind the headline, because, it turns out, Urban also carries a very large guitar. Although the pictures were snapped eight years ago, Urban's famous wife, Nicole Kidman, just saw them for the first time recently and according to reports was "impressed."

Burt Reynolds – June 1981

In 1981, everyone's main mustachioed stud Burt Reynolds appeared on the cover of Playgirl and gave an interview, which included the topic: "His Love Affair With Sally [Fields] Is Not Over." It would be one year later. But inside, Burt did not disrobe. He already had — not for Playgirl, but for the famous 1972 Cosmopolitan shoot, which featured a hirsute Reynolds naked (his left arm strategically placed), reclining on a bear-skin rug, a cigarette dangling from his mouth. Sure, he could have tried to top himself in Playgirl, but really, why mess with perfection?

Jim Brown - September 1974

The September 1974 issue of Playgirl featured a four-page foldout of the former Cleveland Browns football player-turned-actor Jim Brown. Jim didn't do the normal celebrity Playgirl cover up. Nope, he let it all hang out, resting on the edge of a grand piano, inexplicably standing on a spiral staircase, looking thoughtfully out a bay window, jauntily leaning on a candelabra, and posing on the obligatory animal-skin rug.

Tommy Chong – January 1982 

The "Celebrity Nude" headline on the cover of the January 1982 issue of Playgirl (which featured a photo of Jane Fonda) read "Tommy (Cheech &) Chong Proves He's Not Just a Funny Man." The table of contents took it one step further, goading readers that he's "An off-the-wall comedian with an out-of-this-world body." Stoner girls everywhere must have swooned to see an almost entirely naked Tommy inside the mag. No word on whether the publishers approached Cheech to join him in the spread.

Big Daddy Kane - June 1991

So many jokes spring into our minds when we think of Big Daddy Kane appearing in Playgirl. But the rapper kept his Kane covered by a box of candy in the 1991 pictorial. So we'll have to go with his explanation that his nickname comes from his love of martial arts as a boy. Kane stripped down again the following year, appearing clad in leopard-skin briefs for a very racy photo in Madonna's controversial coffee table book "Sex."

Fabian Forte - September 1973

Perhaps he was attempting to shed that squeaky clean teen idol image that still lingered despite a string of edgy movies in the late '60s, including "Maryjane," "The Wild Racers," and "The Devil's 8." So singer Fabian appeared in the altogether in the September 1973 issue of Playgirl, enjoying a dip in the pool and straddling a Honda CB450. Someone definitely listened when he sang "Turn Me Loose."

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