Those who have a long list of things to do before they die had better get moving - according to a Christian group which believes it is the beginning of the end of the world today.
Harold Camping, leader of Family Radio Worldwide, claims to have calculated the time and date of "the Rapture" by adding up numbers in the Bible.
While his theory has been met with widespread scepticism, followers of the movement believe Jesus Christ will return to Earth in the coming hours to gather the faithful into heaven.
It is not the first time Mr Camping, 89, has predicted the end, but despite his failed warning in 1994, this time the retired civil engineer from Oakland, California, is adamant he has got it right.
"Beyond the shadow of a doubt, May 21 will be the date of the Rapture and the day of judgment," he said in January.
But others are less convinced, and so-called "rapture parties" have been planned to celebrate what hosts expect will be the failure of the world to come to an end.
Meanwhile, a Facebook page titled "Post rapture looting" suggests: "When everyone is gone and God's not looking, we need to pick up some sweet stereo equipment and maybe some new furniture for the mansion we're going to squat in."
And seeing the potential to profit from the prediction, one website is selling T-shirts marked: "I survived May 21, 2011. You really thought the world would end? Dumb ass."
However, it is hedging its bets on delivery times.
"If the world doesn't end, you'll get your shirt in approximately 10 business days," it promises.