{This is the first in a semi-regular series of posts regarding great cinematic sex scenes as defined by me. This is completely arbitrary and open for interpretation, but so is life.}
Risky Business - Tom Cruise and Rebecca De Mornay
This was a phenomenal 80s movie, and was far better than any project which boasted a plot around a high school kid turning his parents house into a brothel and then throwing a giant sex party to raise cash for a missing glass egg had any right to be. 
Tom Cruise is the student in question, and Rebecca De Mornay plays his love interest and top-notch prostitute who helps him pull off this massive undertaking. The duo have one fine sex scene near the middle of the film where the doors of his parent's house are blown open by some insanely powerful and unseasonable wind, a weather occurrence which doesn't derail Cruise from mounting DeMornay near the living room. 
That one wasn't bad.
But the real show-stopper, the scene which earned "Risky Business" a place among the finest on-screen sex romps occurs near the end of the film when Cruise and De Mornay hop aboard a train.
{Editor's Note: Unfortunately I could find no image of this scene in Cyberspace}
The scene is shot with muted lighting and some slow-mo shots, which underscores the dramatic tension and the conflict within the characters as De Mornay rides Cruise in a nearly empty train car.
The scene was both necessary and hot, which was a stellar combination that earned the mass transit interlude a place among the very best.
-BDS
I disagree with your selection of what is a good sex scene. Risky Business was trash. Throw it away.
But I love the idea of the series.
A little healthy argument never hurt anyone, but that is sacrilige (sp?) about RB.
And you have to remember that sex scenes are like pizza - even when they're bad they're still pretty good.
DeMornay is hot..Tom is not!
Very hot sex scenes, but I personally would have enjoyed another male actor in Cruise's place.
Tom Welling, perhaps? (Clark on Smallville)
Of course pick #1 is Hugh Jackman
I don't remember these scenes...maybe I saw the "tv version" Sounds hot, but Tom Cruise kinda makes me lose my hard-on.
so to speak...
I'm not a big Tom Cruise fan either. Tom Welling, though, is a whole other story ! : )
Kayla - De Mornay is sexy. Cruise doesn't do much for me in that department, but I liked him much better before the couch-jumping incident and he was good in this movie. Tom Welling? Yeah, I know - Superman and all.
Jlee - So to speak, eh? Well, you need to rent the full-scale version as the TV one doesn't do it justice.
Symplyamused - I had no idea there were so many Tom Welling fans out there as I've always been rather ambivalent about him. Ha.
There's an old Merv Griffin interview with Tom Cruise, all fresh faced, in the success of Risky Business. He is humble, modest and sexy. *sigh* Miss that guy. Not sure I've thought of him as sexy since Cocktail. Thanks for the walk down memory lane.
My daughter says she's going to marry him! Watches Smallville ALL day long...
80's low-grade porn. Is there anything better? I sat through so much for so little.
Linda - I bet that's an interesting interview in light of his recent antics, and I own Cocktail on DVD, a truly silly movie that is still extremely entertaining.
Symplyamused - Clark Kent. Tom Welling. The whole Superman thing gets 'em every time I suppose. Ha.
J717 - You hit the nail on the head - so much for so little - yet when it's done well, so damn entertaining too.
I'm with JLee on this one, i don't even recall it, granted i barely remember the movie as I must have seen it a million years ago. I'll wait till your series is finished and rent them all at once....the dude at the movie store will think i'm a big perv ... oh yeah!!!
i don't think i ever saw this whole movie -
does she even have panties on?
welling = hot hot hot
cruise = friggin' psycho
Miss Ash - This could go on for awhile, and I already have one in mind for next week. Maybe you should rent them in batches of 3 lest the movie store clerk call the cops. Ha.
Locomocos - Can't argue with you on the psycho Cruise angle, which is a shame because I hate to sully this movie with his recent craziness (or maybe it was there all along).
And no, I don't believe she was wearing panties - it was the 80s.
I have never watched the movie.
I guess I will get it this weekend!
You could do a lot worse - just remember the time period it was shot in and enjoy.
That has to be one of the best scenes ever. In many ways that movie is still a teenage rite of passage.
I hope it still is, but I'm not so sure these days. Too bad. I own it on DVD.