I thought this was an interesting site that discusses end of world predictions. http://www.humanreligions.info/the_end_of_the_world.html
There are additional links at the end of this page. They should be clickable even if they don't look that way.
Jehovah's Witnesses
Martin Gardner has authored a perfectly good introduction to the Jehovah's Witnesses, which I will quote at length. The JWs initial predictions of the end of the world were based on pyramidology and numerology. This is the use of measurements and dates surrounding the great pyramid in Egypt to predict days. Because the number of potential numbers to use are as plentiful as the imagination, almost any date can be made meaningful. Pyramidology and numerology is thoroughly discredited by mathematicians, and prophecies based on them have had an uncountable number of failures.
An American preacher enormously impressed by Smyth's researches [on pyramid numerology] was Charles Taze Russell, of Allgheny, Pa., founder of the sect now known as Jehovah's Witnesses. In 1891, Pastor Russell published the third volume of his famous series Studies in the Scripture. It is a book of Biblical prophecy, supplemented by evidence from the Great Pyramid. A letter from Smyth is reproduced in which the Scottish astronomer praises Russell highly for his new and original contributions.
According to Russell, the Bible and Pyramid reveal clearly that the Second Coming of Christ took place invisibly in 1874. This ushered in forty years of 'Harvest' during which the true members of the Church are to be called together under Russell's leadership. Before the close of 1914, the Millennium will begin. The dead will rise and be given a 'second chance' to accept Christ. Those who refuse are to be annihilated, leaving the world completely cleansed of evil. Members of the church alive at the beginning of the Millennium will simply live on forever. This is the meaning of the well known slogan of the Witnesses - 'Millions now living will never die.' [...]
To the great disappointment of the Russellites, 1914 ushered in nothing more dramatic than the World War, and the sect lost thousands of members. New editions of Russell's Pyramid study were issues with the wording altered at crucial spots to make the errors less obvious. Thus, a 1910 edition had read, '... The deliverance of the saints must take place some time before 1914....' (p. 228) But in 1923, this sentence read, '... the deliverance of the saints must take place very soon after 1914....'
Judge J. F. Rutherford, who succeeded Russell after the pastor died in 1916, eventually discarded Pyramidology entirely. Writing in the November 15 and December 1, 1928, issues ofThe Watch Tower and Herald, Rutherford releases a double-barrelled blast against it [...] The Judge did not remind his readers in these articles that he, too, had been guilty of a prophetic error. For many years he had taught that 1925 would mark the beginning of the great jubilee year. Alas, it also had passed, without perceptible upheavals. The sect now discourages the sale and reading of Russell's writing, and although members still believe the Millennium is about to dawn, no definite dates are set. ”
- Failed End of the World Predictions for 1914 to 1920 made by the Jehovah's Witnesses, compiled by the Ontario Consultants for Religious Tolerance
- Failed End of the World Predictions for 1925 to 1975 made by the Jehovah's Witnesses, compiled by the OCRT
- Failed End of the World Predictions from 1975 by the Jehovah's Witnesses, compiled by the OCRT