Where do you find the biggest turkeys at Christmas? In the crackers, of course. And what do you get if your crackers don't contain rubbish jokes? A pretty rubbish Christmas, that's what. Letting out a string of collective groans at the dinner table, as tipsy relatives take it in turn to deliver teeth-grindingly awful one-liners is as much part of festive tradition as family rows, binge-eating, and not watching the Queen's Speech.
In the spirit of seasonal consumerism, British cracker manufacturers whose industry is worth some 120m churn out tens of millions of crackers a year. And whatever their place in the market, from Fortnum & Mason's hand-quilted, pearl-encrusted fabric Paragon crackers (1,000) to the pile-them-high damp squibs handed out at canteen Christmas lunches, they all have one thing in common: a terrible joke.
It wasn't always so. Invented by a London confectioner called Tom Smith in the 1840s, crackers originally consisted of a single, unamusing almond sweet in a twist of paper. They sold well and competition grew, leading Smith to include romantic mottoes in his product. He later put the explosive " crack" into crackers, as well as silly hats and trinkets; jokes appeared in the 1930s.
So what is the secret of a decent Christmas cracker joke? "It's simple," says Julian Reed, whose Robin Reed cracker company has supplied retailers, including Selfridges, Paperchase and Heal's, with 10 million crackers a year since 1975. "They can't be funny. The point is they are supposed to be groan-inducing, not side-splitting."
For Mr Reed and his team, the annual meeting of their joke committee is the highlight of the year. "It's a bit like the Booker Prize," Mr Reed says from his West Midlands headquarters. "We put together a shortlist of jokes we think might be unfunny enough to put in next year's crackers, and whittle it down to 30." Many of the jokes they settle on are sent in by keen customers. "Some people naively think we'll send them money if we use their jokes," he adds.
Mr Reed's rejects this year range from those that fall dangerously close to funny ("What smells of fish and goes round and round at 100mph? A goldfish in a blender.") to the plain stupid ("Is the squirt from an elephant's trunk powerful? Of course, a jumbo jet can keep 500 people in the air for hours at a time.")
Last week, the men's magazine Nuts asked readers for the best (worst) cracker jokes. The winner (loser): What is Santa's favourite pizza? One that's deep-pan, crisp and even.
Professor Richard Wiseman, a psychologist at the University of Hertfordshire, says such jokes are popular because they give bad-joke tellers a rare chance to get a laugh. "If you give somebody genuinely funny material to deliver to a group, they get anxious," the professor says. "With bad jokes, you are expected to get a groan, which is much easier to get than a laugh."
Last year, Professor Wiseman polled 2,000 people and found that self-proclaimed bad-joke tellers prefer to tell cracker jokes, rather than normal ones. The opposite was true in the case of those who told "good" jokes.
"Cracker jokes are a peculiarly British phenomenon," he adds. " It's part of our habit of celebrating the mediocre. When I've explained the notion of telling unfunny jokes to a group at Christmas to American students, they just cannot understand why anyone would want to do that."
At Robin Reed, Julian and his team are putting the finishing touches to next year's batch of crackers, which he will take to trade shows as soon as the office Christmas tree is pulled down. "We're always looking for new jokes," he says. "Feel free to send some in. There is only one condition: they have to be rubbish." Here is a selection of the worst.
Bang! It's another bad joke...
On which side do chickens have the most feathers?
What kind of paper likes music?
What's white and goes up?
A confused snowflake.
What do you call a woman who stands between two goal posts?
Did you hear about the man who bought a paper shop?
It blew away.
What's furry and minty?
A polo bear.
How do snowmen get around?
They ride an icicle.
Who hides in the bakery at Christmas?
A mince spy.
What do you call a penguin in the Sahara?
Son: Dad, there's a man collecting for a new swimming pool.
Dad: Well, give him a glass of water.
Customer: Waiter! Waiter! What's wrong with this fish?
Waiter: Long time, no sea.
Why is it difficult to keep a secret at the North Pole?
Because your teeth chatter.
How do cows subtract?
With a cow-culator.
Why did the teacher wear sunglasses?
Because her pupils were too bright.
What do ghosts play at parties?
Haunt and seek.
Why can you never play jokes on snakes?
You can never pull their legs.
What do you call a crate of ducks?
A box of quackers.
What school subject are snakes best at?
What did they call the crazy golfer?
A crack putt.
How do you cook sausages in the jungle?
Under a gorilla.
What lies at the bottom of the sea and shivers?
A nervous wreck.
What do vampires sing on New Year's Eve?
Auld Fang Syne.
What kind of jokes does a chiropodist like?
What did the dentist say when his wife baked an apple pie?
Can I do the filling?
What sort of vegetables do plumbers fix?
What do you call a multi-storey pig pen?
What is black and white and noisy?
A zebra with a drum kit.
What's the fastest thing in water?
A motor pike.
What is wet and slippery and likes Latin American music?
A conga eel.
What do you call a blind dinosaur?
Do you think he saw us?
What lies in a pram and wobbles?
A jelly baby.
What do they sing at a snowman's birthday party?
Freeze a jolly good fellow.
What kind of sweet goes swinging through the jungle?
What does Santa Claus use to weed his garden?
How do you start a teddy bear race?
Ready, teddy, go.
Why did the turkey join the band?
Because it had the drumsticks.
Why do bakers work so hard?
Because they knead the dough.
What's the most popular gardening magazine in the world?
What do you get if you cross a skeleton with a famous detective?
What do you get if you cross an orange with with a comedian?
Peels of laughter.
What sort of fish performs operations?
What would you get if all the cars in the USA were red ?
A red-car nation.
What's worse than a giraffe with a sore throat ?
Centipede with sore feet.
What is green and stands in the corner ?
A naughty frog.
When is the best time to buy a chicken?
When it's going cheep.
Customer: "This steak is terrible. I want the manager."
Waiter: "Sorry sir, he isn't on the menu."
What do you call a fairy who hasn't had a wash for a week?
What do you get if you cross a cowboy with an octopus?
Billy the squid.
What do you get if you cross a hen with a bedside clock?
An alarm cluck.