-- there's plenty more good stuff to go look at over there, so please visit them. This is taken from Mental Floss' book,
, published in Neatorama with permission.
Whether it’s two billion years from now, when the Sun will no longer provide enough heat to support life on earth, or two hours from now in a nuclear holocaust, life on earth will inevitably come to an end. All religious traditions grapple [wiki] with this fact. Here’s what they’ve come up with so far. Christianity
Things Get Bad: At least according to the Book of Revelation, things will be very bad indeed. Weeping, gnashing of teeth, rending of garments, blood in the streets, etc. All of this will occur during "the Tribulation [wiki]."
And Then: the Second Coming of Christ, wherein Christ - to quote the Nicene Creed - "comes again in glory to judge the living and the dead."
Until: the Rapture [wiki], wherein all Christians (or at least good ones, depending on your particular denomination) are moved from earth directly to heaven with no dying or passing Go.
Islam
Things Get Bad: The Last Judgment in Islam is known as the Qiyamah [wiki]. At a time of God’s choosing - no one knows when - Jesus (yes, that Jesus) will come down from heaven, end all wars, and kill ad-Dajjal [wiki] (Islam’s equivalent to an Antichrist).
And Then: Each and every person who ever lived will be bodily resurrected and judged by God. Those found wanting will be sent to hell either temporarily or permanently; those who have been good and faithful go to heaven.
Until: No, that’s it, actually. For the record, most Muslims do believe that some "People of the Book," that is, Christians and Jews, will also get to heaven.
Judaism
Things Get Bad: The end of days [wiki], or acharit hayamim, will be marked by conflict and tumult. When? Well, the Talmud states that the world will only last 6,000 years - so many Orthodox Jews believe the world as we’ve always known it will end in 2240 CE.
And Then: All of Israel’s enemies will be defeated, the twice-destroyed Temple will be rebuilt [wiki], the dead will be resurrected, and the Jewish Messiah will become King of Israel.
Until: God intervenes in the Battle of Armageddon, saving the Jews, evil leaves the world, and earth becomes perfect. It’s like Belinda Carlisle song: "They say in heaven love comes first/We’ll make heaven a place on earth."
Buddhism
Things Get Bad: According to the Buddhist holy scripture, the Tipitaka, we’ll know the end of the world is coming when morality disappears and people start following the "10 
Amoral Concepts." Those concepts? Theft, violence, murder, lying, evil speaking, adultery, idle talk, covetousness, greed, and perverted lust. Um, uh-oh.
And Then: Once morality disappears, things will degenerate into misery.
Until: A Buddha named Maitreya (known in English as the "future Buddha"), the successor to the Buddha we all know and love, will arrive on earth and begin teaching the pure Dharma.
Hinduism
Things Get Bad: Most Hindus believe that we are currently living in Kali Yuga [wiki], the Iron Age, or age of darkness. 
Unfortunately for us, that means that evil is on the upswing. Eventually, Vishnu will become incarnate for the 10th and final time. By then, karma will have been completely turned on its head, with good people suffering needlessly and the evil rising to ranks of power.
And Then: Shiva [wiki], "the Destroyer," will dissolve the evil and corrupt universe. And then, because all things are cyclical, the universe will simultaneously be reborn.
Until: We start getting evil again and get ourselves into another age of darkness. Most Hindus are careful not to put an exact time frame on eschatological matters. If you do, you can end up looking awfully foolish …
Not the End of the World: People and Groups Who Falsely Predicted the End-time
Can’t Keep Those Davidians Down
In 1942, a Seventh-day Adventist named Victor Houteff [wiki] broke away from the church with 11 followers and founded a "Davidian" branch of the church in Waco, Tex. Davidian. Branch. Waco. You see where this is going. But what a winding path the church took.
After Houteff died, his wife prophesied that the world would end on April 22, 1959. In point of fact, about the most interesting event of April 22, 1959, was the Yankees’ Whitey Ford [wiki] striking out 15 Washington Senators en route to a 1-0 victory. Several hundred members of the Davidians left after the non-Apocalypse, but - remarkably - dozens remained faithful. In 1962, Benjamin Roden [wiki] became the group’s leader and proclaimed himself successor to not only Ms. Houteff, 
but also to King David, noted star of the Hebrew Bible. Roden’s wife became the new Davidian (get it?) when she took over the church. She quickly declared that in the Second Coming, Christ would assume the body of a woman.
You’d think by now the group would have theological whiplash, and yet it stayed together until 1981, when Vernon Howell, who would later rename himself David Koresh [wiki], showed up. By the time the ATF raided the compound in 1993, the Branch Davidians had 130 members. While their numbers dwindled after the massacre, Davidianism is still alive: A few people still claim to follow Koresh’s teachings.
Go Ahead, Drink the Kool-Aid.
Jim Jones, cult leader of the People’s Temple [wiki], portrayed as
the loving father of the "Rainbow Family"
By now, "Don’t drink the Kool-Aid" is a well-known admonishment not to buy into collective wisdom. It derives from the 1978 Jonestown massacre, when 914 followers of Jim Jones [wiki], included 276 children, committed suicide. But here’s the thing: No one at Jonestown drank Kool-Aid [wiki]. They drank cyanide-laced grape Flavor Aid, a Kool-Aid competitor - but the poor, innocent Kool-Aid man has been taking the fall ever since.
