With summer's daily deluges, you've probably spent more time wringing out your soaked sneakers than pondering global water shortages. But the day you read this, the world's human population will consume 3 trillion gallons of water. And not a whole lot of it is what you'd call "clean." The U.N. Environmental Program estimates that 15 million children die each year from foul water. Here at home, we're slurping down disease-causing microorganisms in every glass from the tap. Marine species are going extinct. And pundits project that the major wars of this century will be fought over a substance that falls from... More >>>