I once spent several hours researching a similar question. My findings are here.
Teri Weigel is also notorious for being the first Playboy Playmate to do hardcore porn. I believe that the playmates are contractually not allowed to do hardcore porn, so this was kind of a big deal.
I’d bet the Tom Cruise/Nicole Kidman tape was leaked on purpose. It’s like, with all those gay rumors, and at that point having had kids only by adoption, he felt a need to tell the world, “See, I do so fuck my wife!” 
Interesting. Did Playboy sue her? Could they? I mean, once you’ve been Playmate of the Month, they can’t exactly take that away from you, the copies of the issue are still out there.
Variety regularly runs an ad from a company claiming they’ll help celebs raise their profile by helping them create (!) and market sex tapes, ‘accidentally leaked’ or no.
Why it’s simply amazing that she doesn’t have that little bit of information posted up right outside her office! 
Poor thing. I wonder why she didn’t jump onto the convention circuit? Just about everyone who had a featured role in as few as only one episode of TOS has managed (it seems; I don’t know anything about the economics involved) to eke out a living by going from con to con.
What Tom Cruise/Nicole Kidman tape are you talking about?
Hard as it is for people to believe today, there was a time when Star Trek was nothing to the world, except as something to point and laugh at. There were no conventions and no way to make money from the series. It took almost two decades for the phenomenon to begin.
I remember Star Trek fandom being already big in the 1970s, with national and regional conventions, and several fanzines. The first Star Trek convention, in New York in 1972, was a sold-out success. And Trek fandom got only bigger every year after that.
I’ve never seen it but I remember it in the news. It was when they were still married, so it must have been 2001 or earlier.
I’m gonna need a cite on this one. If only to see Nicole when she was still incredibly hot. I never heard of such a tape existing.
Joey Heatherton isn’t a perfect match to the OP, but comes awfully close. Promising up-and-comer in the late 50s-early 60s, did a lot of variety shows of the Perry Como/Andy Williams variety, almost nabbed the Lolita role that went instead to Sue Lyon. She never quite caught on with her own generation, though, and her attempts at a comeback got more and more desperate, bottoming out with The Happy Hooker Goes to Washington (Not quite porn, but a magnet for performers whose careers were in freefall in 1977).
She wasn’t quite the Lindsey Lohan of her era; closer to its Jessica Simpson, right down to the controlling dad and the tabloid marriage.
I’ve never heard of a Kidman/Cruise tape either… So, cite?
I cannot think of any movie stars that have gone to porn, but here in Denmark we have a story of the opposite: Katja Kean. She was a porn actress, but has since establish herself somewhat as an actress in Denmark.
You could say it predated that, since the second season was the result of a letter writing campaign by fans.
IIRC, the Cruise/Kidman “sex tape” was just footage related to Eyes Wide Shut and not actual nookie material.
Well hey, it’s Denmark. 
When I went there 2 years ago even nude sunbathing was considered sorta stodgy and passé.
(BTW, is it me or does her birthname “Sussi Le Cour” sound even more blue-movieish than “Katja Kean”?)
Speaking of sex tapes, is there any one in the world would believes Screech’s tape was leaked, and not put out specifically by him to get money? And does this idiot not realize that when people buy a celebrity sex tapes, its because the celebrity particiapants are hot, and that no one is going to pay 40-50 bucks to see a dork have sex with two anonymous prostitutes?
Uh, you’ve just described pretty much the entire, highly successful porn career of Ron Jeremy.
It still took until the 80s for there to be a convention circuit, with appearance fees large enough for the secondary cast members to make money doing it. If you think about the economics, it’s clear that you need enormous conventions with very high attendance fees just to be able to give out money. For an individual to make a living at it, you need to have these all over the country. Why should it be surprising to learn that a decade or more was necessary to make the economics feasible?
Third and last season, after almost being cancelled in the second season. But the third season was so awful except to the most deluded, um, devoted fans, that the continuation may have hurt rather than helped.
Also, don’t forget Traci Lords (perfectly safe link), who started out in porn films as a 16-year-old ( :eek: ), but has so completely emerged from that “ghetto” that she’s done guest spots on such far-from-porn TV shows as Gilmore Girls and Will and Grace.
Lords, though, is probably a good object lesson in why washed up celebrities don’t do porn. Lords is the most successful porno actress to move to mainstream, and she basically went from being an A list porn star to a C list TV actress. Someone who started out as a successful mainstream actress can probably do as well as Lords without doing the porno.