Build-it-yourself text messaging system. Admittedly, Ken Banks doesn't know much about health. What he does know a lot about are open source programming and mobile networks. With them he built FrontlineSMS, a free software platform that lets you build private text messaging networks with only a laptop, a mobile modem, and a bunch of cell phones. Install the software, plug in your phone to your PC, input phone numbers of people you want to reach--like patients or nursing staff--craft a message, and hit send. You're now a text message jockey. The best part is that it's two-way, so recipients can reply to you to ask questions. You could also run surveys. Ken built FrontlineSMS with developing countries in mind, were Internet access is poor. It has been used for elections monitoring in Nigeria, by aid workers in Afghanistan to alert each other of Taliban attacks, and in Zimbabwe, Iraq, Cambodia and El Salvador. In 2007 Josh Nesbit heard Ken speak at Stanford. Inspired, Nesbit and friends have since customized Ken's source code to make FrontlineSMS:medic. At a clinic in Malawi, doctors doubled the number of TB patients they could see with the time they saved by not having to leave the clinic for basic rounds. In the U.S., rural physicians, or primary care doctors on a budget, could use this to communicate with patients (take your meds!) or with colleagues. It requires GSM, but if you're within these AT&T or T-Mobile coverage areas, you're good to go.

"There are some meaty challenges in global health, but there are also some simpler problems that can be solved. Like just giving health workers the ability to communicate, [so] when a doctor leaves the hospital he can to order a blood test. There are some simple things you can do."