So this thing is really, really awesome, and, of course, I immediately thought of possible trail-application of this device once it's available. Small, light, easy access... In a larger demographical use, though, it could be one of the greatest inventions of the century:
link:
www.engadget.com/entry/1234000890054889/
and another story:
www.gizmag.com/go/4418/1/
In a nutshell:
"A device about the size of a large pen or drinking straw, the LifeStraw is a complete water purification kit that draws its power from the person sucking down the water."