You know what I’m talking about. Those magical times when someone inadvertently sets you up with a perfect straight line…and you instantly respond with the perfect zinger? Oh, and there are others around to appreciate your wit? It does happen, but nearly often enough.
A woman once asked me if I knew any contractors who did “roofing on the side.”
I said, no, he does it on the top!
Your examples?
We were doing The Music Man one summer. There’s one scene where the women of the town were doing some sort of tableau. The dialog goes, “One Grecian urn, two Grecian urns, three Grecian urns, and a fountain.”
The director called a halt and one of the women in the scene asks, “What a Grecian urn?”
I piped up “About a buck and a half an hour.”
I had something of a George Castanza moment in a very crowded movie theater. I was seeing the second Matrix movie, I believe, with several friends. And a trailer comes on and concludes with its title: “2 Fast 2 Furious.” And I automatically shouted out, “Two hours too long!” I was a cinema legend for about 30 seconds. I’m not exactly known for my public outbursts, so it surprised the hell out of me and my friends, but damn everyone seemed to have a good laugh.
A friend and I were discussing… um… amorous histories.
He made some sort of bragging statement about how when he’s done “they can’t get up and walk afterwards anyways”.
To which I deadpanned “Then I suppose you should make the knots a bit looser.”
He cracked up for about 5 minutes.
Mine was a touch mean, but I will mention it none the less. A lesbian friend of mine asked me to take her to a rather formal affair that she was certain that her former husband would be attending. Her ex was not a nice man and she was still not completely comfortable being “out”, so in the old fashioned parlance, I was her beard. I was visiting with some of the people at the cocktail party when into the circle I was in came the ex obviously looking to embarass the guy out with his former wife. “It’s so nice to see my ex out with a man for a change.”
“Yes,” I responded with unusual quickness, “I understand she has never been out with one before.”
He was laughed out of the get together. And I have never had so many drinks bought for me in my life. Apparently he was not a well-like individual.
At the elementary school I attended the morning announcements would conclude with “the joke of the day”.
One particular day, the joke was “What wriggles at the bottom of the ocean?”
This is an old standard in children’s joke anthologies, and the answer is “a nervous wreck”.
Before the announcer could get to the nervous wreck punchline, one of the kids in my class yelled out “Moby’s Dick!”
Even the teacher was laughing at that.
I was out at dinner to celebrate a friend’s birthday, and for whatever reason my entree was served on a large plate, while all the other entrees were served on small plates. My friend’s girlfriend looked at my plate and asked me why mine was bigger than everyone else’s; I told her it was good genes. She turned bright red and everyone else burst out laughing.
I was in a college French class when we started talking about the German airplane manufacturer Fokker. A girl asks “Fokker? What’s Fokker?”
I explained “You see, when 2 people care a great deal for one another…”
One day in the lunchroom of a large auto parts warehouse I worked at in my early twenties, one of the guys was talking about having been hired to go to work at the new Goodyear Rubber Co. plant. Someone asked what he would be doing there he said he was gonna be a “rubber tester”. I said, “Oh, yeah? Do they still have openings for medium and large?” There was a saucy, good-looking, stripper-esque sort of girl working there at the time who was sitting across from him and who spewed milk all over the table.
He did NOT find that funny. 
Once in a meeting, someone said that a project could be done in 12 weeks.
I asked if he meant Earth weeks.
Once, while teaching at a Jewish private school, I had a migraine come on. One of my friends, the English teacher stopped by and saw how bad it was for me and offered to take the kids. She took them on a walk through of the building, stopping in the art room where there was a very large map of the world, and she talked them through a chunk of European history.
When she returned my students, I had cold, wet cloths on the back of my neck, had covered my eyes, plugged my ears, and turned off all the lights.
“I got them all the way up to the Spanish Inquisition,” she said.
“Nobody expects the Spanish Inquisition,” I croaked.
The poor sixth grade boys just could not get why she nearly fell over laughing.
At work, we have a long-standing tradition of naughty jokes, dirty repartee, and generally immature behavior. So when my co-worker comes up to me and asks, “Appleciders, I have a question,”, and I deadpanned back, “About nine inches.” Everyone died laughing. It was excellent, and I’m glad no one took offense, because I didn’t think about it- it just popped out. Damn, I enjoyed that.
Mine was when I was talking to my African-American friend (I’m white as milk) Raquel. Don’t remember what prompted it, but this was the exchange:
Raquel: John, you’re the blackest white boy I know.
Me: Why, because I have a huge dick or because I’m broke as hell?
Raquel: You a damn fool.
I think the way she said the last line was actually the funniest part of it.
I was at a sci-fi marathon this winter, and the gist of the event is that they show fairly terrible movies and everyone MST3Ks at the screen.
My best line this year was during Moonraker, where the scene goes from Bond dropping into bed with a girl straight to him rolling off her and checking his watch (presumably because he had to be somewhere.) When he did that I yelled “Forty-two seconds. My best yet!” - which was a fairly obvious thing to say but no one else thought of it. I had them rolling.
Two of them.
When I was on Okinawa, a bunch of us were eating at the local restaurant across the street from the base. One guy ordered spring rolls and about halfway through one he paused, fished around in his mouth and hauled out a quivering strand. “There’s a rubber band in my spring roll,” he complained.
“Musta run out of springs.”
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My D&D group was on a dungeon crawl when we were attacked by a naga. It was more powerful than we were ready for so we had to pull out all of the stops, basically surrounding it and hacking away with all our collective might. After it expired, the DM commented as he was toting up the XP, “Too bad you slashed up the skin so much; it’s valuable.”
“Really?” from one of the newcomers.
“Certainly,” I shot back. “Where do you think naugahyde comes from?”
Two in particular. The first was when my friend Paul was walking toward the bathroom at our fav cafe and I happened to be walking behind him, on my way to another friend’s table. He turned and said “you’re not going to follow me into the bathroom, are you?!”
I replied. “Heck no! I don’t want to shatter my illusions!”
The second was on The Guy, Dave. We were talking to a co-worker and I mentioned that we’d gone out the night before. Dave turned around and said “We? Who is this “we”? Ya got worms?!”
I looked him up and down and snapped off “Just the one, dear, just the one!”
Co-worker nearly fell over. Heh.
On the subway, I was sitting on a newspaper when someone came up to me and asked “Excuse me, are you reading that?”
I stood up, flipped a page, sat down again,and said “Yes, I am.”
Not sure about best but most recent was a woman at work telling us that she was going out at lunchtime to have botox injections in her face. I said that it sounded like a risky procedure. She assured us that the guy giving the injections was a doctor, that he was highly recommended by her friends, that they assured her he was an artist.
And I said, “Let’s hope he’s not Pablo fucking Picasso.”
I was in the Navy sitting at a desk typing on a word processor. Various things like rulers were stored in the drawer in front of me. One of my co-workers walked up and said “Hey Evil, gimme a ruler”. I immediately responded “King of Spain” as I continued to type.