US president Donald Trump declaring war on North Korea — not funny.
Ekant Veer and his wife changing their Facebook relationship statuses from "married" to "it's complicated" — fewer people harmed, but still not funny.
But disgraced politicians rising again, spaghetti growing on trees, Burger King toothpaste and seeing double on Auckland's skyline?
That's funny and harmless and you can expect a whole bunch of carefully crafted pranks and hoaxes to roll out today, April Fool's Day.
Veer, a University of Canterbury associate professor in marketing, April Fool's Day connoisseur and most definitely happily married husband, says his hope is everyone takes the day in the manner it's intended — as an annual chance to have a bit of harmless fun.
"The best ones are the ones that cause very little harm. They might cause a bit of emotion and hysteria but not necessarily overtly offensive ones. If Donald Trump decides to ... declare war on North Korea on April 1 and then go 'haha, it's just a joke', that's actually not that funny."
Same goes for the trick he and his wife always talk about playing on unsuspecting friends and family — changing their Facebook relationship statuses from "married" to "it's complicated".
"We realised it might be a little too mean for the extended family. They'd start getting worried and we'd have to say."
April Fool's gags that really worked balanced perfectly between ridiculous and believable, and the mechanics of the mind filled in the rest.
"There's a lot of confirmation bias in it ... people want to believe them."
We've been pulling the wool for quite a while, although no one's quite certain how long.
According to History.com, some historians think the day — also known as All Fools' Day — traces as far back as 1582, when France switched from the Julian calendar to the Gregorian calendar.
Those failing to grasp that the new year now began on January 1 became the target of jokes, such as having paper fish put on their backs and being called "poisson d'avril" (April fish), believed to symbolise easily caught fish.
Other historians link the day to ancient Roman festival Hilaria, where people dressed in disguise, or speculate a connection to the Northern Hemisphere spring equinox, a time of unpredictable weather, according to History.com
In modern times, it was mid-last century, as mass media cemented its influence over widespread populations, when the tradition took hold, Veer says.
The BBC has a lot to answer for.
Hit Google for the top April Fool's jokes and the famously strait-laced broadcaster's 1957 spaghetti tree harvest is consistently named no.1.
The three-minute hoax report, delivered in perfect received pronunciation, of a Swiss family harvesting spaghetti prompted a massive response from wannabe growers.
CNN would later call the fake spaghetti harvest "the biggest hoax that any reputable news establishment ever pulled".
It wasn't the first media-produced April Fool's prank — the annual celebration of silliness has proved perfect fodder for radio hosts for decades, including then 1ZB's Auckland Breakfast host Phil Shone, who warned listeners in 1949 that a mile-wide wasp swarm was descending on the city.
Listeners were warned to wear socks over trousers and leave honey-smeared traps outside, and some were so alarmed they flooded police and the Department of Agriculture with calls.
News reports quote police, who twice called the station asking for the broadcast to stop, describing the joke as "silly".
Maybe, but it did no harm to Shone's career — he'd notch another decade in the flagship show.
Still, it's the spaghetti prank that really stands out for Veer.
"That was probably the start of mainstream media getting into it. It wasn't just you playing a prank on your friend. It started to become newsworthy.
"People were trying to cause mass hysteria ... and when you see that mass hysteria, that's kind of funny to people, whether it's in a positive or a negative way."
There's no doubt April Fool's pranks can spark mass hysteria, usually, but not always, harmless to all but the ego.
A retrospective on the prank published 40 years later by Juneau newspaper Capital City Weekly explained local prankster Oliver "Porky" Bickar waited three years for a clear April 1 to fly hundreds of stockpiled old tyres into the crater and strike a match.
The long-suffering British were again targeted three years later when The Guardian published a seven-page supplement devoted wholly to San Serriffe, a nation said to be made up of a group of semi-colon shaped islands and dominated by its two main islands, Upper Caisse and Lower Caisse.
It even supposedly had a Kiwi link, after the supplement's designer based the fictional islands on New Zealand, according to US website Museum of Hoaxes.
"The success of this hoax is widely credited with launching the enthusiasm for April Foolery that gripped the British tabloids in subsequent decades," the website wrote.
The game was up when the iceberg was towed into Sydney Harbour — rain started to wash away the "iceberg's" firefighting foam and shaving cream exterior, revealing white plastic sheets beneath.
Other memorable trickery on April 1 includes US fast food giant Taco Bell taking out ads in 1996 to say they had bought the country's treasured Liberty Bell, soon to be renamed the Taco Liberty Bell.
Instant colour TV could be obtained, thanks to a new technology, by pulling a nylon stocking over the screen, viewers were told.
Stocking raids ensued, but it would be another eight years before colour really arrived.
The modern version of the better TV gag, for time-poor 2017 audiences, came via streaming service Hulu, who announced a new series "Hu", which cut hit shows down to eight seconds.
Kiwis have also copped their fair share of April Fool's Day trickery, from KFC sushi to Sky City's twin towers plan.
Last year New World came up with a novel way to help vertically challenged customers.
"We're stoked to announce a world-first. All New World stores will soon have in-aisle trampolines, allowing our shorter customers to grab those top-shelf items with ease!", the company announced on Facebook.
The Herald had some fun of its own the same day, publishing a story about a planned zipline from One Tree Hill to Cornwall Park — where thrillseekers could whizz down the side of Maungakiekie at barely-believable speeds of more than 190km/h.
At AUT, holographic lecturers were suggested, Burger King promoted Whopper burger toothpaste and Waikato District Police announced their new Tactical Bunny Unit crimefighting squad.
It's no surprise that anyone and everyone has jumped on the April Fool's bandwagon, Veer says.
Handled with care, it's good publicity.
"It's become just a different way that people, especially the media or brands, can draw attention to their products in a lighthearted, fun way in the hope that this is going to lead to positive beliefs and brand equity associated with it."
All he can suggest for a wary public is to just try to enjoy the joke, even if they're caught up in it.