Some of my favourites can be found here, especially the sys admin and mathematician jokes. (Caution: the thread is rather long and some of the replies are off-topic.)
A personal favorite, though it relies on just the right, wild-eyed delivery:
Q: How many Vietnam vets does it take to screw in a lightbulb?
A: You don’t know because you weren’t there, man!
Q How many Episcopalians does it take to screw in a lightbulb?
A Two. One to mix the cocktails and one to call the electrician.
Q How many Madison Wisconsin east-siders does it take to screw in a lightbulb?
A. Three. One to change the bulb and two to talk about how much better it was in the sixty’s.
Q: How many technical support personnel does it take to change a light bulb?
A: We have an exact copy of the light bulb here, and it seems to be working fine. Can you tell me what kind of system you have? OK. Now, exactly how dark is it? OK. There could be four or five things wrong… Have you tried the light switch?
One old one that appeals to a limited audience:
How many Japanese junior high school students does it take to change a light bulb?
One that I just made up:
How many small-town business owners does it take to change a light bulb?
Answer: That light bulb has been burning fine for years. It’s those new florescent bulbs that are driving the light away.
Q: How many Deadheads does it take to change a lightbulb?
A: None. They just wait for it to burn out, then follow it around for 20 years…
Q: How many therapists does it take to change a light bulb?
A: Therapists don’t change light bulbs, therapists encourage light bulbs to change themselves.
Q: How many Nixon aides did it take to change a light bulb?
A: [expletive deleted]
Q: How many Reagan aides did it take to change a light bulb?
A: I have no recollection of that.
How many Californians does it take to screw in a lightbulb?
None. Californians screw in hot tubs.
Straight from the factory floor:
Q. How many engineers does it take to screw in a lightbulb?
A. “That’s maintenance! (CLICK!)”
Q. How many maintenance techs does it take to screw in a lightbulb?
A. “I’m on a break! (CLICK!)”
Q. How many Dallasites does it take to screw in a lightbulb? A. All of 'em. One does it, and the others talk about how *great* the new lightbulb is!
I forot my all-time favorite:
Q: How many actors does it take to screw in a light bulb?
A: Eleven: one to screw it in, and ten to stand around talking about how much better they could have done it.
Q: How many Republicans does it take to change a light bulb?
A: Who knows? But once it’s changed, it’s gonna be so great!
Q: How many Libertarians does it take to change a light bulb?
A: Keeping track of such statistical information is an unjust intrusion on one’s privacy. Mind your business.
How many Canadians does it take to change a lightbulb - none they’re happy living in the shade.
How many Southern Baptists does it take to screw in a light bulb?
But they’d better be a married, heterosexual couple. No one else has any business screwing anything!
Some White Wolf ones here.
The best one:
How many Black Furies does it take to screw in a lightbulb?
One to change the bulb and three to frenzy over the violation of the socket.
Q: How many Feminists does it take to change a light bulb?
A: None, the bitch can cook in the dark.
Q: How many Irishmen does it take to screw in a lightbulb?
A: Three, one to hold the lightbulb and the other two to start drinking until the room starts to spin around.
Why did the punk rocker cross the road?
Because he was stapled to the chicken.
GOLDEN RETRIEVER: The sun is shining, the day is young, we’ve got our whole lives ahead of us, and you’re inside worrying about a stupid burned out light bulb?
BORDER COLLIE: Just one. And then I’ll replace any wiring that’s not up to code.
DACHSHUND: You know I can’t reach that stupid lamp!
LABRADOR RETRIEVER: Oh, me, me!!! Pleeeeeeze let me change the light bulb! Can I? Can I? Huh? Huh? Huh? Can I?
MALAMUTE HUSKY: Let the Border Collie do it. And you can feed me while he’s busy.
POODLE: I’ll just blow in the Border Collie’s ear and he’ll do it. By the time he finishes rewiring the house, my nails will be dry.
COCKER SPANIEL: Why change it? I can still pee on the carpet in the dark.
MASTIFF: Mastiffs are NOT afraid of the dark.
CHIHUAHUA: Yo quiero Taco Bulb.
IRISH WOLFHOUND: Can somebody else do it? I’ve got this terrible hangover…
POINTER: I see it, there it is, there it is, right there…
GREYHOUND: If it isn’t moving. Who cares?
AUSTRALIAN SHEPHERD: First, I’ll put all the light bulbs in a little circle…
ENGLISH SHEEP DOG: Light bulb? I’m sorry, but I don’t see a light bulb.
GERMAN SHEPHERD: All right, everyone stop right where you are! Who busted the light? I SAID, “STOP RIGHT WHERE YOU ARE!”
HOUND DOG: ZZZZZZZZZzzzzzzzzz
CAT: Dogs do not change light bulbs. People change light bulbs. So the question should be: How long will it be before I can expect light?
Q: How many Monty python fans does it take to change a lightbulb?
A: Nine. One to say that it is an ex-lightbulb and it is no more. One to say it’s just resting. Three to burst in and say their chief weapons are fear, surprise and rutheless efficiency. One to say he didn’t expect the Spanish Electrician. One to do a silly walk, one to say “And now for something completely different”, and one to change the lightbulb.
Q: How many mathematicians does it take to change a lightbulb?
A: One, who fetches nine Monty Python fans, thereby reducing the problem to a previously solved joke.
Longshoremen does it take?
Twenty three. You got a problem with that?
Zen Masters does it take?
Two: One to screw in the light bulb, the other to NOT screw in the light bulb.
Mystery writers does it take?
Two: One to change the bulb, the other to give it an unexpected twist at the end.
Software engineers does it take?
As many as you want, but you have only 4 man-months to finish the job.
Quality Assurance people does it take?
We don’t actually fix the bulb, we just report that it’s burned out.
Microsoft executives does it take?
Eight. One to change the bulb, the other seven to make sure that Microsoft gets two dollars for every light bulb replaced on earth.
Windows users does it take?
Only one, but he’ll swear up and down it was just as easy for him as a Macintosh user.
Newton users does it take?
Foux! There to eat gravy, axe ladle soup.
Elephants does it take?
Um, elephant jokes are passe
How long will it take a computer field tech to change a light bulb?
That depends on how many burned out bulbs he brought with him.