Let's take Terral: He sells a newsletter for $25 a year. 1000 subscribers (some say it was a lot more) = 25,000 a year.

If you have a little phantasy you can make up a lot of scenarios.
The orbit of Comet Elenin was well known. Make some doom of it by making it a brown dwarf (or the precursor of a BD).
Adapt the idea (from others) that Leonid Elenin is not a real person and the name stands for Extinction Level Event - Nibiru Is Near and you have a nice conspirathy.
Now look for alignments of Earth-comet-planet (what happens quite often) and tell some bullshit about big earthquakes +/- 3 days around the alignments.
And if there is a 5+ something (that happens statisticaly once a week) the tards are excited.
And because of the "hits" more tards are coming and more newsletters are sold ...

Of course most tards see the hoax after some time when the prophecies fail - but just create a new hoax and other tards will come.

It just starts with C/2012 S1 (ISON)*.
The religious-tards are already on it and the doom-tards will follow soon, trying to make profit.


*
I have copyrighted the term "Invasion Soon - Oncoming Nibiru" and I will sue everybody who uses it.



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