This thread prompted me to break my years-long lurking career.
Wife and I had one a number of years ago. We were driving through the central Montana countryside, one of the small two-lane highways that crosses the state and has NOTHING but the occasional ranch on it for miles--and if it's early on Sunday, you are more than likely the only car in the county.
We'd been on the road for a while (I was driving), talking about random stuff, when the conversation turned to sex. (Because I'm a guy, and that's all we think about.) I can't remember exactly how the subject came up, but I had just seen an article somewhere about some women who got arrested for driving around bottomless and mentioned that to her.
Her comment was not what I was expecting, since she's normally very conservative in dress--she said that sounded exciting, as long as she wasn't fully out in public and only MIGHT get spotted.
That got me thinking. We hit a lull in the conversation, and I decided to take a chance.
"So, about being naked in public where you might be spotted...how about like in a car on a deserted Montana highway?"
She gave me a wide-eyed look--apparently, the question was quite unexpected--and asked "What!?!" So I was more direct--"You heard me, take your pants off."
Slowly, as if she couldn't believe she was doing it (I sure couldn't!) she slid her shorts down off her legs, leaving her in one of her nice Victoria's Secret panties I love her to wear--a nice dark blue set of bikini briefs, not a thong but tight across the ass, high on the hips and narrow in the front. She sat that way for about 30 seconds, almost like she was working up her courage, before she quickly slid her panties off and put them on the floor by her shorts and shoes.
It was a nice summer day, and with the sunroof open, her nicely trimmed peach-shaped pussy (she sports a small landing strip) looking beautiful in the sun. I started to compliment her, thanking her for stripping for me and telling her how sexy she was.
By this time we'd moved a little closer to the mountains, and traffic started to pick up, as this was one of the main roads through the Rockies to the west side of the state. I deliberately slowed down, so the cars behind us would have to pass us, giving the drivers (it was Montana, so most were driving pickups) and opportunity to at least glance into our sedan and see Wife not wearing any pants.
We drove that way for about 15 minutes, me talking about how sexy she looked, she talking about how she liked the feel of the leather seats on her bare ass, and me occasionally fondling her tits and pussy. Suddenly, she surprised me by leaning forward, unhooking her bra, and taking both bra and tank top off in one smooth motion--all while a long row of cars were going by in the other direction! She sat there in the passenger seat, with both a little blush of embarrassment on her face but a smirk of pleasure on her lips, as if it was just another day trip with her husband.
I let her enjoy the sensation of the hot sun on her bare tits for a couple of minutes, then started fondling them again. She leaned back, spread her legs, and started rubbing her clit, all while we were doing 55 down the road. Once again, I slowed down a little, irritating the people behind me who decided to pass us. I had two pickups (obvious ranch hands) who gave me the thumbs up, and one older couple (in their 80s) who didn't even notice.
Wife was getting really excited at this point, and I told her to stop because she was leaving me out of all the fun. She sat back up, leaned over, and unbuttoned my shorts, dragging my dick out of its confinement. I, of course, had been rock-hard for the last 20 miles, so when she started stroking me it felt like heaven. She eventually leaned over and tried to suck me, but the center console and steering wheel got in the way. Still, for a couple of minutes, she was stretched out across the two front seats, ass kind of in the air, highlighted by the direct light coming through the sunroof, as cars and trucks went past us in both directions.
She sat back down in her seat, still naked, occasionally playing with herself. Watching her do that, in full view, made me almost crazy with lust. By this time, we'd moved out of the plains and into the mountains. I'd done some scouting on Google Earth earlier, and realized that we were fast approaching an unimproved rest area at the top of the pass we were approaching. Without telling her why, I pulled over and up about a 100 yard road into the trees, where there was a clearing, a fire pit, and a couple of picnic tables. Making sure I parked so her door was facing the road, I grabbed a blanket and got out of the car, telling her she need to get out so I could fuck her cross-eyed. She jumped out of the car...just as a slow-moving semi came around the corner of the road below us, with about ten vehicles behind it. My wife was busted, in plain view of everyone going up the pass!
She ran around the car to me, where I had spread the blanket. It was an amazingly good day, weather-wise, the kind of day to make you want take off your clothes and be in the sun. She didn't make any comment about the cars, she just got down on her hands and knees and begged me to fuck her. Of course, what's a gentleman to do?
We were both so horny we didn't last long. A couple of minutes later, we both came explosively and simultaneously, my wife crying loudly (she's a screamer) and me thrusting as hard as I could into her sopping pussy. We both laid down on the blanket for a couple of minutes afterwards, enjoying the glow of sex and the warmth of the hot sun. About ten minutes later, we both got up, cleaned up, got dressed (yes, she put her clothes back on), and continued our trip.