You throw money where it makes the biggest difference. This is not going to be the neediest person in the world, but I'm not sure exactly how bad they'll be.
Judge the charities on a case-by-case basis, and see what works best. Once you do that, you will spot patterns, and you can work from there. Don't assume it works the same as healing a wound.
I'd be really interested to hear what the Less Wrong community thinks of this. Don't spoil it by reading the comments first.
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