Earth is not a very stable environment these days -- politically or environmentally -- and it follows that a fair number of end-of-the-world predictions are being made.
That being said, history has seen several periods of political or environmental unrest in the past, and yet, here we all are.
In any case, some of these things are interesting:
December 21st 2012. According to the ancient Mayan "Long Count" calander, this will be the end of this current age of the world, or B'ak'tun. However, it is not likely that the Mayans believed that the world would actually end on that day, since archeologists have found references to much later dates. Also, their calendric system allowed for a nearly infinite number of days in the "long count," most of which were simply never used because they're irrelevant. In any case, December 21st is slated to be a big day for change.
A baktun, if I understand correctly, is a period of thirteen 400-year periods (5200 years). It is interesting that almost exactly 400 years before 12/21/2012, the astronomer Simon Marius first saw Andromeda, our closest galaxy, through a telescope (I don't think the 400-year periods were supposed to have any significance though). A big first step towards modern astronomy. So this current baktun began in 3188 BC.
3000 BC, roughly, marked the beginning of the early bronze age in Greece, the begginning of the Jiroft Civilization (in ancient Iran), Egypt's first dynasty was established, Construction of Stonehenge was started, cuneiform writing is developed in Sumeria, bronze is discovered, the abacus is invented, silk is produced for the first time, and generally across the globe there were advancements in the fields of agriculture, literature, and warfare. This is also roughly when the Julian Calendar begins.
Also, interestingly enough, there is a lot of evidence that there was a major climate change that occurred around the same time. For one thing, before 3000 BC, the Sahara Desert wasn't a desert. Also, one Baktun before that, in the 8th or 9th millenium BC, there was a period of post-glacial global warming.
Now, Hindus have some interesting ideas about time. There are things called "yugas" (trans. roughly as "ages"). And there is a certain amount of disagreement as to when the yugas start and end, and how long they are. But according to one view, the current Yuga began in roughly 3000 BC. Now, this viewpoint goes along with a belief that the current yuga is a dark, nasty one that will last for the next 427,000 years, roughly. So screw that.
Now of course, another view states that we're already in the next, less-dark yuga, and the previous dark one was only 2,400 years long, and began around 700 BC. So it must have been the one before that that began in 3000 BC. This is interesting, but according to this logic, the next new age won't begin until 4100 AD, so it doesn't quite match up with the Mayans. It's all a bit irrelevant since the Hindu concept of time generally doesn't really include apocolyptic Ends. Although there is a unique branch of Hinduism that predicts the world will end in 2036 AD.
(700 BC would correspond roughly with the advent of the the Iron age. The middle of the 2,400 year yuga would then fall on 500 AD, and it would end in 1700 AD. Thus, the "dark age" would start with the iron age, and span through the medieval era, and go right through to the end of the rennaissance. Dark times indeed.)
Anyway, that was a pretty extensive sidetrack. this was supposed to be about the future, not the past...
So, the jewish calender points to the year 2240 as the time when creation (which began 5766 years ago) will come to an end. What sort of end, I'm not sure, but apparently you're going to want to miss it.
Evidently, the teachings of Buddha are slated to last only 5000 years after his (first) life. After all remnants of the Buddha and his teachings are forgotten or destroyed, a new Buddha-like saint will come to re-awaken the teachings. So if Buddha lived around 500 BC, then 4500 AD would be when that change will happen. Not really an end of the world prediction, but there you have it. Speaking of Buddha, the Dalai Lama has recently been dropping hints that he will choose not to reincarnate himself after he leaves his present body.
Christians seem very eager for the world to end. The first Christians thought the end would come in their lifetime. Then there were several other dates they decided on, and then nothing happened. Of course in 1000 AD and 2000 AD there was a lot of hooplah and nothing happened. Interestingly, attempts at predicting the future were frowned upon by Christ Himself, apparently.
Various American Indian tribes had doomsday prophecies that were deemed fulfilled when the white man came. Enough said, if you ask me. The end of time is relative, assuming Einstein got it right.
Ahh okay that was a bit longer than I meant for it to be.
Now, I'm not going to mention any current events, but ever since the proliferation of nuclear weapons we've been on the brink of global destruction. Right?
Well, what of it? That's what gets me. regardless of what has been prophecied in the past, we have been living for decades now in a world where we could actually unleash the kind of nastiness that people could only dream of in the past. It makes it all seem pretty moot don't you think?
Einstein said, "I don't know what weapons will be used in world war three, but in world war four people will use sticks and stones."
I take some comfort in that thought, ironically.