Not really in the spirit of the OP, but…
The Blue Angels are practicing today. A few minutes ago I heard an F/A-18 fly by, and the sound of an emergency vehicle’s siren. I said to my coworker, ‘He’ll never catch him.’
When I was bagging groceries for a rather bitter cashier (due to recent rejection by a man) at the grocery store she rather loudly announced to her customer and the world at large that, “men are a disease.” This annoyed me a great deal and immediately said, “Well how lucky for you that you can’t catch it.”
Nice try. I heard this joke years ago.
My parents were fighting about some damn thing or another. The argument got longer and louder and my father shouted, “Do you want a divorce?”
Without batting an eye my mother shot back, “No, I want to stay married and make life hell for you!”
We’ve handed down that line like a family heirloom.
My sibs and I and several nieces/nephews were sitting at the dinner table honoring our parents’ 50th wedding anniversary. Mom said, “Thanks for coming.” I said, “Thanks for having us!”
This is my favorite witty reply this week:
Entering a class full of students during a break, talking to the previous teacher. I would be teaching the same students in the same class next period. This teacher had told me previously she had a handful of kids that always held her after class, asking her questions.
Me: Hey! Why don’t you guys stay after class and ask ME questions?
Student: Do we have a test tomorrow?
Me: I dunno.
Last month:
A big burly co-worker was talking about a huge convention happening down the street.
Him: You know, if I was a transvestite hooker, I could make a lot of money.
Me: You’re never too old to follow your dreams.
We just got back from a week in Hilton Head, which was having record high temperatures. The ocean was like bath water. My wife happened to come close to me and said “the water seems cooler over here”… I responded… “Sorry, I just peed.”
I’ve posted this before.
In the late 70s I went to Italy with a tour group. One day when we were in Rome, we had some free time. I said I was taking a side trip to the Protestant cemetery to see the graves of Keats and Shelley. A woman asked, “Oh, were you an English major?” I replied, “No, I speak it.”
I was with a friend when her husband called in her cell. After they chatted, she turned to me and said, “He’s in Latvia. He’s riding the Riga ferry right now.”
I said, “I hope for your sake he’s talking about a boat.” She practically choked laughing.
I was at a Pagan gathering in eastern Ontario, one of the centerpieces of which was Women’s and Men’s Mysteries. The Men’s Mystery involved a lot of running and jumping and climbing trees and such, at the end of which one of the men would be crowned the mock-king of the gathering. I had less than no interest in this and was hanging out with some friends when this guy came by and asked me, “Hey, are you participating in the Men’s Mystery?” “No,” I told him.
“Why not?” he asked. “Don’t you want to be King?”
“What for?” I retorted immediately. “I’m already a queen.”
It might not have been my wittiest riposte ever, but my most lucrative:
I was assistant sales director for a hotel, doing some work at my desk, when a colleague © poked his head in my office door and asked whether I had a second to step into my manager’s (H’s) office briefly. I popped around the corner, and C asked me whether I’d ever heard of Barry White. I said “Of course,” and named a couple of his more famous songs…
C looked at H, and said “I told you so,” and the two of them told me that H had never even HEARD of Barry White. I paused a couple of beats, looked at H (who would have been in his twenties throughout the 1970s,) and said “You weren’t getting much during the seventies, were you?” C and I dissolved into laughter.
A few days later, C (who was to be the general manager of a new hotel that our company was opening later that year) offered me a job as a full department manager in the new hotel. Some time later, after we were on-site in the new property, he admitted to me that he was only considering me as a candidate for the job until I asked that question of H. At that time, I told C that my pause before the question was a mental editing of the first thing that popped into my head: “You’ve just confirmed that you really ARE the whitest man I’ve ever met.” C nearly died laughing.
I miss working with that gang!
At a department meeting, in early December. One of the team leads, Shin, is passing out some documentation relating to the project we’re working on.
Shin: I got one for each of you - Merry Christmas!
Laura: I didn’t know Santa Claus was Chinese.
Me: Where do you think he gets all those toys?
Not exclusively mine, but my GF and I were in a parking lot in Hollywood, and a couple of guys holding clipboards came up:
“Do you mind if we ask you some questions?”
GF: “No problem.”
“What is the most obvious thing about me?”
GF: “You are a Sceintologist.”
We both bust a gut. I love that woman.
I was working in auto parts warehouse once and there was a guy there who was sort of a jerk - a loudmouthed, obnoxious, in-your-face kind of guy. One day during lunch break I was sitting at a table with several other people, including a pretty foxy girl who was sitting directly across the table from me. He comes in, gets his food and pulls up a chair next to the pretty girl and starts babbling about how he’s gettin’ out of that frickin’ place (the warehouse) and going to work at the new Goodyear plant that had just been built. Someone asked what he was going to be doing there and he proudly said “I’m gonna be a rubber tester.” Without even thinking I found myself blurting out “Oh, yeah? Do they still have openings for medium and large?”
The hot girl shot milk out of her nose.
And if looks could kill I would’ve been vaporized on the spot. 
More recently, I was in a 7-11 one day getting a Big Gulp after having spent several hours doing yard work in 100+ degree summer heat. Not to put too fine a point on it but I looked like I had just stepped fully clothed out of a swimming pool. A woman heading to the fountain area suddenly spotted me, stopped, and said “Man! You are hot!” I said “Thanks! You’re not so bad yourself.”
In a technical drawing class, a classmate was having trouble with the assignment.
Her: Ugh, I can’t do this! I’m going crazy!
Me: Going?
She and the teacher both cracked up laughing.
One time I was riding in the car with my sister and I placed a travel mug on the dash to tie my shoe. My sister is kind of wound tight and she yelled, “that cup’s not stable!”
I replied, “that’s not the only thing in this car that’s not stable.” Like all great retorts it came with a price.
Him: What’s your favorite place to relax?
Me: Home.
Him: What’s your least favorite place to relax?
Me: Home.
Him: Huh?
Me: …with my wife.
One of my favs from 2003:
Me: Who do you think I should add to my fantasy basketball team?
Him: Why don’t you add _______?
Me: He’s got a hamstring injury, his career’s over!
Him: Magic Johnson had hamstring problems for years.
Me: Yeah, and look what happened to him!
So would he.
My favorite spur of the moment retort was at my last job. One girl is known to make crass and rude jokes at other people’s expense. Normally they’re pretty funny, sometimes they just border on rude. Well one day we were all hanging out shooting the shit, and in the course of conversation she said to me “I bet you’re a crier. Do you cry after sex?”. Without even a pause I said “The only time I cry after sex is when I’m putting the money on your nightstand.”
Ooohs all around.
The workplace Christmas party was coming up in a week, a friend of mine, in his 50s, balding & with a tendency to make really dated jokes is going around asking everyone if they plan to wear a lampshade on their head. Most of them are much younger & have no idea that was once an old cliche’ about boorish party behavior. Finally, I say “Well, Paul- you’re the only one here who’s head most resembles a light bulb!”
Another time, they gave us meat & cheese trays in the lounge. I was having lunch with Paul & we were speculating about the safety of the food. I nuked my ham & cheese sandwich while he just ate his without heating it. I muttered “Hey salmonella! Party in Paul’s colon in 10 minutes!”
Both times, Paul laughed louder than anyone else.
Also at work, my friend Owen who is always getting one over on me, mentioned his 20th wedding anniversary is the next day. I say “Congratulations, Owen… and my condolences to Jean.” His response- “For once, I don’t have a comeback ready… But when I do…!”