No, I don’t mean pointing and sniggering, either.
I have noticed that after making love, I tend to get the Satisfied Woman Giggles[sup]TM[/sup], in which the silliest things will make me laugh like a maniac. So, fellow dopers, am I a maniac, or do you do this, too?
Well, I can’t claim to ever have had the Satisfied Woman Giggles [sup]TM[/sup] – the thing I’d be giggling at was the fact I had a penis, in that case. 
However, I’m familiar with the syndrome you’re talking about. I’ve seen it happen in women, and I’ve had similar things happen to me (I guess those would be the Satisfied Man Giggles [sup]TM[/sup], yes?) so I suppose it’s not terribly uncommon – at least among the erotically skilled.
I’ve had that too! I think it’s like laughing when you get off a roller coaster–it’s not because it’s funny, but just because it’s so much * fun*. Just a guess.
I sometimes get mad teeth chattering after a big orgasm.
Brynda, you’re not a maniac. Nothing better than a bout of laughter while on an endorphine high 
Well, I guess I’ve experienced the down side.
First girl I ever had sex with laughed while she was coming. For your very first time to end with an outburst of laughter is, to say the least, HIGHLY disconcerting. I hate to admit, but since I was sexually inexperienced and mentally immature, I didn’t react well. Got pretty angry, actually. Plus, it was her first time, too, not to mention the fact that she was fairly repressed and not able to talk comfortably about sex, so she wasn’t able to reassure me that she wasn’t laughing at me.
It’s alright, though. Later, fate made up for it by sending me a girl who got VERY energetic after sex. Passionate energy and intensity of feeling, the kind that let me first hear the words “Let’s go again”. Guess that’s the ‘endorphine high’ TM mentioned.
Not only do I experience this, but my husband and I have a running joke about it, since the laugh is invariably followed by, “shit - hand me a Kleenex!”
Or was that TMI?
Mostly pre sex laughter, here. 
I frequently laugh during and after sex (I’m multi-orgasmic), and I will now officially incorporate Satisfied Woman Giggles ™ into my vocabulary.
I do this, for the reason expressed so economically by MrO. I’ve never been with a woman who did it, though, and at least one of my partners was offended; she thought I was laughing at her.
It’s good to see I’m more normal than I thought I was.
This is me: He He BOOM(the sound of my head hitting the pillow.)
Same here…not so much laughter as much as I get the giggles about everything. The better the sex, the more giggly I get.
Guilty, big-time. Have freaked out some of my partners, which, of course, makes me laugh all that harder. Some join in, some think something’s wrong, some get mad… It usually embarasses me, but damn, it’s fun. 
Esprix
It’s only natural to laugh when you’re having fun, I just end up grinning, usually for a long while afterwards and occassional little giggles when I think back to it.
Kitty
Giggling is one of my responses to high energy or anxiety, wherever it may come from.
I’ve gotten better at it, at some previous points, it would actually escalate from giggles into -very- audible laughter. You have no idea of some of the strange looks I’d get after sex, or while getting blood tests or performing dissections in the Bio-Lab.