While doomsayers hunkered down to await the coming apocalypse, others took a more lighthearted view on Friday of a Mayan prophecy of the world's end and marked the event with stunts and parties.
Interpretations of the Mayan "Long Count" calendar point to an era of more than 5000 years coming to a halt on 21 December, although in Sydney it was business as usual.
With Australia one of the first countries to see the sun rise on what is supposed to be the end of days, Tourism Australia's Facebook page was bombarded with posts asking if anyone survived Down Under.
"Yes, we're alive," the organisation responded to fretting users.
Scientists in Taiwan also had their tongues firmly in cheek, setting up a two-storey replica of a Mayan pyramid and planting an electronic countdown timer on top, drawing crowds at the National Museum of Natural Science.
Australian Prime Minister Julia Gillard set the satirical tone this month with a one-minute spoof address recorded for a youth radio station.
"My dear remaining fellow Australians, the end of the world is coming," she intoned.
"Whether the final blow comes from flesh-eating zombies, demonic hell-beasts or from the total triumph of K-Pop, if you know one thing about me it is this - I will always fight for you to the very end."
In Asian capitals, many planned to party like there's no tomorrow with apocalypse-themed dinners and pub nights.
Hong Kong's Aqua restaurant promised to pick up the tab for its HK$2112.12 ($273) six-course meal if the end is nigh - though patrons will have to stump up if still alive at midnight.
Pubs from India to Malaysia have got into the doomsday spirit, with one in Kuala Lumpur hosting an "End of the World" party with global tunes until it all ends.
But although most saw the funny side, with an explosion of humourous banter on Twitter, elsewhere many worried that the ancient civilisation's calendar really will herald a fiery finish to human civilisation.
US space agency NASA has been contacted by thousands of worried people asking for advice on what to do. In a web page devoted to debunking the Mayan prophecies, it reassured them that the world will not end in 2012.
"Our planet has been getting along just fine for more than 4 billion years, and credible scientists worldwide know of no threat associated with 2012," it said.
NASA's reassuring words were lost on those who headed to a number of towns around the world designated safe zones from the impending disaster, and others who took refuge in mountains or bunkers, or stockpiled guns and survival kits.
The village of Sirince in western Turkey has become an apocalyptic magnet, with all 400 hotels in the area fully booked. It is reputed to be doomsday-proof because the Virgin Mary is said to have risen to heaven from there.
Likewise the picturesque south Italian village of Cisternino, singled out by an Indian guru as a safe bet come the end of the world.
The apocalypse is also being taken seriously in parts of China, where UFO enthusiasts will gather in the southern province of Hunan to perform a "Mayan ritual" to attract alien visitors, the state-run Global Times reported.
But there has also been a darker side, with China arresting some 1000 people in a crackdown on a Christian sect that spread doomsday rumours and urged followers to slay the "red dragon" of communism.
Social networks have also been buzzing in South Korea with a spoof "prophecy", attributed to the 16th-century French seer Nostradamus, that ties "Gangnam Style" singer Psy to the Mayan apocalypse.
Thousands of people were expected to flock to the Mayan ruins at Chichen Itza in Mexico before daybreak Friday - some to hail the start of a new Mayan era, others to bid farewell to the world.
Even though officials said no special celebrations were planned to mark the turn of the Mayan calendar, which happens to coincide with the Winter Solstice, up to 20 000 revelers were awaited at the pyramids.
The 21 December mystery stems from a carved stone found in Tortuguero, a Mayan site in Mexico. The relief contains a cryptic allusion to something really big happening on Friday.
However, most experts interpret the calendar to mean 21 December 2012 is simply the end of a 5200-year era for the Maya and the start of another.
If that's right, everybody can relax and make sure end of times will be the best of times.