I like how these two posts go together:
I waited four years for a teacher to ask, “Can anyone use ‘loquacious’ in a sentence?”
Hey Joe, where you going with that bun in your hand?
I work at a restaurant. One of the line cooks is named Joe. It’s only a matter of time.
I want to give my warden a plaque, with our Institution seal on it. Under it, the “dog latin” motto: FABRICATI DIEM, PVNCTI AGVNT CELERITER, which (sort of) means “Make the Day, the Moments Pass Quickly”.
However, during the presentation, part of the plaque inscription will “accidently” break away, leaving the motto to read: FABRICATI DIEM, PVNC
As a fan of the original BBC “The Office”, the correct answer for “weaknesses” is: eczema
Bumper sticker:
JESUS SAVES
All others take full damage
I’ll quote George Carlin:
“If you knew someone who was a homosexual and they were in an accident that left them paralyzed, you could always comfort the family by saying, 'Well, he was a fruit. Now he’s a vegetable. At least he’s still in the produce aisle”
:ducks and runs:
Or if you knew a guy named Robert who was a quadruple amputee, you could push him into a pool. And so on and so forth.
I have this bumpersticker.
JESUS LOVES YOU*
Everyone else thinks you’re an asshole.
heh, that was me. I can’t believe anyone remembers that. I should change this sig line soon as I’ve been using it for awhile.
I’ve done this. Either those people hear it all the damn time (in which case they should change the question) or it’s not as funny as we think.
I’ve used something similar many times, which never gets a laugh:
“Do you have anything for a headache?”
“No. Why would you want a headache?”
Here’s one I get use out once or twice a year. . .
After someone tells a joke, pipe in with, "Hey I’ve got one! Say, ‘Knock knock.’ "
Having just heard or told a joke, someone present usually goes for it, which leads to the inevitable, “Who’s there?” Something about the person being put on the spot to tell a knock-knock joke gets me every time. 
I was in line at a Subway during the lunch hour rush yesterday and the people working behind the counter were trying to coordinate themselves to make the assembly line go faster. They were doing the “do you want it toasted?” thing and the lady at the head of the line was telling her co-worker guy “I put it in, you take it out.”
I so immediately wanted to blurt out “That’s what she said!” but I was behind some woman in a business suit and in front of a mom with her kid. Opportunity wasted. 
In Through The Looking Glass And What Alice Found There, Lewis Carroll begins one of the greatest poems in English thusly: 'Twas brillig and the slithy toves/Did gyre and gimble in the wabe. Years later he defined most of the unusual terms in the poem. The wabe, he said, was the area around a sundial and it was called this because it went a long way before and a long way behind the sundial. When I first read this I was determined that some day I would use the word “wabe” in its proper context. Years passed , I was in college, drinking beer with some of my friends on the campus lawn. Someone asked where the churchkey was. I looked around and saw that it was on the grass next to a sundial. I couldn’t believe my good fortune. I cleared my throat and as I was about to say majestically “It is over there, on the wabe.” someone else blurted out, “There it is, on the grass next to the sundial.” For fifty years I have been looking for another opportunity to use that word!
By the way, do college students today know what a “churchkey” is?
It’s one of those little metal things you used to use to open cans before you didn’t need to use those anymore, isn’t it?
My mother has one. I think it’s called a churchkey.
Not this one.
Being of Chinese descent (he said with more awkward phrasing than was strictly necessary), I’ve always wanted to go to a small public performance of A Midsummer Night’s Dream, and when they get to the line,
I want to yell out “HEY!,” then sit back down.
If I ever get a brain tumor (bad) I’ll be waiting to meet with the doctor so I can finally trot this one out (good):
“This should be a relatively simple procedure, right? I mean, it’s not brain surgery.”
This is probably a more likely situation to arise at one point, than to be collaborating closely with NASA engineers from the JPL.
That’s the whole beauty of “that’s what she said.” There’s never a bad time to use it! (That’s what she said!)
See?
Heh, that’s what she said.
Hey, you’re right!
I once was a technical support tech for a popular drawing program. When we got a call, we’d see the customer’s information on our screens. I got a call once from the Johnson Space Center, from a woman who needed me to explain how to draw a straight line–The single easiest thing to do in any drawing program, and something covered in the first paragraph of the second section of the manual (first section was on installation, of course).
As a customer servant, I just couldn’t. But I spent the whole call wanting to say, “Really, lady–It’s not rocket science!”