Over 6,000 people die a day (most of them children) from water releated illnesses. These folks have created The LifeStraw, a straw about the size of a small clarinet that can be worn about the neck and weighs about 0.095 Kg (3.3 ounces). It’ll filter 2 liters (half gallon) a day for about a year! And they only cost about $3 each.
Over a billion people in the world don’t have safe drinking water! (Drinking salt water will reduce the life expectancy in half).
More info (from the FAQ):
I spotted this on the New York Times video feed I get on my TiVo.