A business out of doing your business?

There are many reasons why the United Nations created a World Toilet Day (October 19th).  Most of them are pretty straightforward – bringing awareness to the simple disease prevention, environmental, and social benefits of having a sanitary private place to do your business.  Some of the benefits are surprising – such as having a direct positive correlation with girls attending school.  We can all understand how a toilet can raise our quality of life.  But when the Bill Gates foundation announced a “Reinvent the Toilet” competition with one of the requirements being that the toilets need to cost no more than a nickel a day to operate, several of the new designs proposed the unthinkable – making profit from waste.  Some business from your private business concepts: make fertilizer, generate electricity, and even farm high-protein grubs for animal feed!