Kind of a weird topic, but I’d imagine that a real-life menage a trois is probably completely different than the imagined one. For those that have participated, what was the most surprising thing about it? What was completely different than you expected or imagined?
That it’s really hard to concentrate on more than one person at a time and get any physical pleasure out of it yourself. The psychological pleasure is still pretty good, though.
(Also under the header of questions I shouldn’t be answering on the SDMB.)
Getting the bill?
The guilt afterwards. The couple were in a meaningfull relationship and the guy didn’t take the follow up emotions too well. She wanted to do it again and he took it as a sign that she wanted to be with me. Then I started feeling bad about it too.
It takes a very special relationship for this type of thing to ever end well.
I don’t recommend it.
Wasn’t as fun as I expected.
I take it you enjoyed your time here? 
-Tcat
That Jodi and psycat90 enjoyed it so much.
We are talking about the wine, right?
I can’t say anything about it surprised me. Except wondering why I hadn’t done it sooner.
How many knees and elbows were in the way. There were three of us, and at least 23 elbows, I’m sure of it. 
Serious answer: the intensity of a woman’s orgasm when viewed from the outside. Holy shit! I could feel the heat radiating off her body in these pulsing waves, and I asked our male companion if it was always like that. He grinned and said, “Only when you do it right!”
That being in the middle is every bit as much fun as they say it is.
Me, too.
Started very casual and quickly became toxic. Weird little head-games, like being over at the husband’s parents’ place for movie night and having him (out-of-the-blue) lift up my T-shirt to display the scratches on my back to his parents. (We were sitting on the floor and they were on the couch.)
Also, she got very emotionally attached and made a big scene when I got myself a one-on-one girlfriend and opted out. Married-with-children and acted like I’d been cheating on her. 
With another couple, what surprised me the most was that the dude wanted to give me a little attention, too. Had known them for months and never had the slightest hint. Clue me in before everybody’s naked, at least! He quickly adjusted his approach when it became clear that it wasn’t going to go down that way, but still… that scenario didn’t get repeated a whole lot more.
That my girlfriend at the time was incapable of seducing any girl that did not look like Jodie Foster. Ehhehh, she was so hot but she’d go off to talk to something cute and come back with Jodie Foster. I wasn’t surprised when she went fullblown lesbo down the road.
Disclaimer: Any current or future statements or insinuations that Jodie Foster does not appreciate men sexually runs counter to my deepest fantasies and will therefore be summarily ignored. Thank you.
Oh, wow, gee, thanks. The last “you know who you look like?” comment I got was a very excited man telling me I look “just like the teenage Jodi Foster” I thought I couldn’t be more offended, but thanks to you, I am…
I think the fact that it was me, a chick, and another dude was what suprised me. I was always like
“Well, if it ever happens, it would have to be with two chicks.”
It’s not that I was homophobic or anything, but I do not find men attractive, especially penises. But this summer I was visiting a friend, and him, his GF, and I all got pretty toasted, and what started off as midnight skinny dipping in his apartment complex’s pool, turned into a naked shower, and then a threesome. Although, even while drunk, he was of sound enough mind to say that he didn’t want me and her to have penile-vaginal sex, just digital stimulation and oral. In the end, it wound up being him doing her missionary style on the bed and her head tilted to the side to give me some oral action. Looking back at it now, it’s clear that the doggy-style position would have been much more conducive to a proper three-way.
That managing* two women is more than twice as much work as managing one.
And I would agree that it takes the right relationship to even consider it.
[sub]*Servicing? I’m not sure of the proper verb choice here.[/sub]
Well, the dog was a little skittish afterward …
I woke up before it got to the fun part. 
Similar to bouv’s expectations, but worse: while I was happy to share a naked chick with my buddy, I didn’t want to see his erect dick, or him to see mine, so after a while I left him to it (it turned out she wanted to be “spit roasted” by us). I was only a teenager though.
I’m not sure if I want to know what that means…