Sometimes, it's the simplest technologies that have the greatest potential impact on people's lives. Take the Vestergaard Frandsen Group's mobile personal filtration system, otherwise known as LifeStraw. It is a powder-blue plastic tube—much thicker than an ordinary straw—containing filters that make water teeming with typhoid-, cholera- and diarrhea-causing microorganisms drinkable.

The filters, made up of a halogenated resin, kill nearly 100 percent of bacteria and nearly 99 percent of the viruses that pass through LifeStraw. A University of North Carolina at Chapel Hill evaluation tested the device's performance in water containing Escherichia coli B and Enterococcus faecalis bacteria and the MS2 coliphage virus as well as iodine and silver. The results indicated that LifeStraw filtered out all contaminants to levels where they don't pose a health risk to someone drinking the water.

But the device does not filter heavy metals such as iron or fluoride nor does it remove parasites like cryptosporidium or giardia, although the Switzerland-based company's CEO, Mikkel Vestergaard Frandsen, says there is a version of LifeStraw available to relief groups in Bangladesh and India that can filter arsenic.

At less than 10 inches (25 centimeters) long, the device can filter up to 185 gallons (700 liters) of water, estimated to be about a year's supply for one person. The device is no longer usable when its filters become too clogged to pass water through, typically after a year of hard use.

The success of the personal filtration system led Vestergaard Frandsen to introduce earlier this month its LifeStraw Family device, an instant microbiological purifier that provides about 2.6 gallons (10 liters) of safe drinking water in an hour and about 4,000 gallons (15,000 liters) over its life span for a family of six. LifeStraw Family is designed to sieve dirt, parasites, bacteria and viruses, and will be available starting in May.

The next step is promoting LifeStraw technology so that nongovernmental organizations (NGOs) and aid groups will buy and distribute them. This is no small task, given that the need for clean water is not promoted as heavily as AIDS prevention or literacy training in some developing countries, Frandsen says, adding, "No one is stepping forward to be the rock star of diarrhea [eradication]."

But LifeStraw was recognized by Saatchi & Saatchi's public relations arm as the top "world-changing idea" in a recent competition of technologies impacting medicine, education and aid work. Vestergaard Frandsen Group received $50,000 from Saatchi, plus another $50,000 worth of the PR firm's marketing services.

Saatchi, which is owned by France's Publicis Groupe, SA, chose LifeStraw over a field of competitors that included a reusable controller to improve the distribution of IV fluids, a collapsible wheel that can be folded down for easier storage when not in use on bicycles or wheelchairs, an energy-efficient laptop designed for children in developing countries, a 3-D display that uses special optics and software to project a hologramlike image of patient anatomy for cancer treatment, an inkjet printing system for fabricating tissue scaffolds on which cells can be grown, a visual prosthesis for bypassing a diseased or damaged eye and sending signals directly to the brain, books with embedded sound tracks to help educate illiterate adults on health issues, a phone that provides telecommunications coverage to poor rural populations in developing countries, and a brain-computer interface designed to help paralyzed people communicate via neural signals.