The latest stage in Bill Gates' ongoing mission to be able to sleep at night despite being one of the richest men in the world is all about sanitation.
It's been said many times before, but Gates is one of a tiny handful of good role models for the super-wealthy: he will die knowing that he had an impact in his business, as most fabulously wealthy people can, but far more importantly that he saved hundreds of thousands of peoples' lives with what he reaped from it.