How to Become a Superhero (and why I will never donate to charity again) (jamesaltucher.com)

I like your strategy but there are small local charities like food banks that can always use money. We give a significant amount every year and doing micro gifts would be very difficult so we research a few charities a give them the majority of our donations.

Sadly, these days homeless shelters and food banks need every cent and most are local and well run.