Bill Gates is betting big that a reinvention of toilets can save a half million lives and deliver $200 billion-plus in savings. Gates explained that new approaches for sterilizing human waste may help end almost 500,000 infant deaths. He also said that it could save $233 billion annually in costs linked to diseases caused by poor sanitation and hygiene. The Bill & Melinda Gates Foundation has spent $200 million over seven years funding sanitation research. It has also showcased some 20 novel toilet designs that eliminate harmful pathogens and convert bodily waste into clean water and fertilizer.