During the halftime show of the Super Bowl. 10+ million people watching from around the world. I’d give Janet Jackson a wardrobe malfunction the world would never foget.
Five bucks says it’s been done at least once in the “vomit comet” used to train astronauts for microgravity. I’d also bet it’s been done multiple times on space stations or even longer shuttle missions. NASA has denied having official “weightless sex experiments” but with mixed crews I’d bet the curiosity of crewmates made if “unofficially” happen at least once.
Enjoy,
Steven
On a roller coaster.
Standing up in a hammock. Or the Oval Office- never mind, that’s been done.
With a space prostitute.
Those considering zero-gravity intercourse might want to check out this somewhat disturbing and yet darkly amusing video of a cat on the vomit comet. Sex in zero-g might be fun, but it would require not just practice but also special harnesses; the whole equal-and-opposite-reaction thing means that neither you nor your partner(s) would remain stationary throughout the physical activity. You’d need to bungie yourselves together or something, lest your encounter be reduced to random groping and banging together, and I don’t mean that in a good way.
Not to mention all the little globules of juice floating about…
On the top of a mountain in the middle of a thunder storm.
In a past life I was a civilian working for the U.S. Army’s housing directorate, and my job entailed measuring vacant living quarters to be sure that the information we had on file matched real life. I became friends with an attractive airman who was working as a housing inspector, and soon had thoughts about doin’ it in an empty house … like in one of the big sunrooms that the flag officer quarters had … hmm, part of me still really likes that idea. 
Then, of course, there’s always the “sex at work after hours” fantasy. Haven’t given up on that one yet! 
In Valinor.
Carnegie Hall, with a soprano.
On your high school girlfriend’s parent’s bed.
IN the center of Stone Henge, on the Sphinx or in the great pyramid, in the catacombs of Paris. As for Disneyland/World the caves on Tom Sawyer Island are nice.
Arthur C. Clarke has noted this (including the harnesses), in his books, but suggests that, once you know what you’re doing, it has great possibilities. In Rendezvious with Rama he notes the exisdtence of a book called the Nasa Sutra.
I like the Space Shuttle and Stonehenge.
How about the Eiffel Tower (probably been done, eh?).
Throne room of Buckingham Palace(not as sexy as it sounds, I done been in thar–it’s not a big throne and the room is just one big empty room with dusty carpeting).
In Hogwarts clock tower–with Lupin, thankyouverymuch.
Red Square? Tianmen (sp?) Square?
in the Taj Mahal–with acolytes to bring food and wine.
This is turning into a fine afternoon for my devious mind…thanks for this thread!
Tony or Carmella?
I’ve also an addendum to my previous answer…any cheesy Tunnel o’Love at the state fair - might as well get a good use out of it.
E.
My friends and I used to have a contest–whoever had sex in the best place won a ceramic shoe that would be passed around from couple to couple. The current shoe-holders had sex in a radio studio while the show was on the air … in front of Greg Brady.
No one will ever get that shoe back. sigh
For myself, castle or cemetery, but thunderstorm is mandatory.
The star in the middle of Texas Stadium.
Surrounded by all but one of the Dallas Cowboy’s Cheerleaders, cheering me on.
I thought you were going to say, “taking turns.”
Where do you work?
I don’t know, I think after all these years it would be sort of awkward.
“Oh, hello, Mr. and Mrs. Johnson. It’s me, Giraffe. Remember, I used to date Sally? How is she doing, by the way? Oh, really, joined a convent? Huh. Oh I’m sorry, how rude of me, this is [Mrs. Giraffe]. Sorry about the bedspread.”
Done that! Nice and springy. Still haven’t done it in a trap harness while on a screaming reach, though.
How about at the geographic center of the United States? IIRC, it’s in the middle of a field in Kansas. Sounds doable.
Out in front of Myanus.