There's another category:
This is not a special case of 1 since by the time everybody's talking about these things it's generally too late to take effective action.
I think none of the things you mentioned are black swans--market bubbles have popped before, banks have frozen before, bail-ins have (I think?) happened before--but I agree that 'impending catastrophes' is a category of things one would like to have the earliest warning of.
The low-probability piece, though, is not the news source but the ability to interpret the information better than everyone else. It seems to me that for the areas one knows well, this probably falls into 2 and 3--if you run a company that depends on online software, you should probably ...
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