Water source is a big problem in most developing countries. Millions of children get sick and many die because of drinking unsafe liquid. Fortunately, technology has produced a very cheap way to make drinking water clean. It's still not perfect, but the LifeStraw can filter and kill plenty of bacteria from water for only three bucks.

This nine-inch gizmo contains layers upon layers of mesh filters to block bacteria, before iodine beads that will kill survivors. There's active carbon too, to remove taste of iodized water. A single LifeStraw can clean up to 185 gallons of water, which should be enough for a year.

With that said, it's not at all complicated to use. Vestergaard Frandsen S.A. company CEO Mikkel Vestergaard Frandsen said, "You have to suck pretty hard at first to get it moist, but after that it's easy."

From making mosquito nets and anti-malaria plastic sheets, this man has come a long way to saving people's lives. "As a businessman, I can be proud to get a contract for 2 million bed nets and fulfill it on time. But as a person, I can be proud that over the lifetime of the nets they will prevent the deaths of 400,000 children," he added.