John Voelcker, an interactive media strategist, released a review of the top ten technologies that are changing the world. His list is based on technologies developed by social entrepreneurs who thought through the development , usability and financing of their solutions. 

Voelcker's list is as follows, followed by summaries (based on his paper) of what these products actually do:

1. The Enviroloo by Enviro Options (Pty) Ltd of Kya Sands, South Africa.

Sewage treatment poses a problem in the developing world. People are exposed daily to disease carrying insects and contaminated water. In response to this problem, South Africa-based Enviro Options Ltd. introduced a new system, the Enviroloo, which uses heat and ventilation instead of a water-based system.   

2. Engine kit by Envirofit International Ltd of Fort Collins, Colorado.

Two stroke engines in Asia are commonplace, as is the resulting smog and pollution. Envirofit International Ltd. of Fort Collins, Colorado, designed a kit which uses a direct fuel injection system to bypass carburetors and directly inject fuel into the cylinders, which allows a substantial reduction in emissions. The product is in the testing phase in the Philippines.

3. Solar Light System  by SELCO Solar Light Private Ltd of Bangalore, India.

Electricity is costly in India and solar systems are generally considered unaffordable to the rural poor. SELCO Solar Light partners with microfinancers and bsuinesses to finance the purchase of these systems to those who would otherwise consider them out-of-reach. 

4. VitaGoat System by Malnutrition Matters of Ottawa, Canada

 VitaGoat, created by Canadian nonprofit Malnutrition Matters, is a system that enables people to stop depending on the unreliable, namely electricity. The system consists of a steam boiler and a generator powered by a bicycle which processes produce into preservable forms that are not susceptible to spoiling.

5. OpenCourseWare by the Massachusetts Institute of Technology of Cambridge, MA.

MIT surprised academia when it put much of its coursework online to be accessed by the public at no cost. When other institutes of higher learning might tighten its grip on its materials, MIT made its work available to everyone, simply to help anyone who wishes to learn, learn.  

6. Solar Powered Microfilm Projector by Design the Matters of Cambridge, MA.

As I mentioned above, electricity is generally a problem for developing nations. Luckily, firms have invested in using solar powered based solutions to create a number of useful technologies. Cambridge, Mass., based organization, Design the Matters, created a "Kinkajou" projector which runs on solar-powered batteries instead of electricity. Inexpensive microfilm is used to teach workers to read at night. 

7. Inexpensive Hib Vaccine, by the Hib Vaccine Team of Havana, Cuba, and Ottawa, Canada. 

Scientists from University of Havana in Cuba and University of Ottawa in Canada teamed up in the mid nineties to think of ways to develop effective, low cost vaccines. According to Voelcker, they were able to make an artificial replica of the antigen through synthesis. The synthetic version has been deemed safe based on research and has been patented. 

8. Adspecs, by Adaptive Eyecare Ltd. of Oxford, England.

Vision problems plague countries where optometrists are scarce or unavailable. Oxford University professor Joshua Silver created adaptive eyeglasses which allows the user to readjust the magnification according to their comfort level. Adspecs are priced at $10 or less and the World Bank is currently looking at ways of helping people finance the purchase through a microcredit program. 

9. Upright steel looms, by the Centre for the Improvement of Working Conditions & Environment of Lahore, Pakistan. 

The idea behind upright steel looms is to create a machine that could easily replace child labor with adult labor. The looms can be easily handled by adults who no longer have to rely on children's small fingers to complete intricate work. Amazingly, a study (based on 30 looms) shows that the child workforce dropped from 60% to 10% and productivity had increased.  

10. IT Telecenters, by CEMINA of Rio de Janeiro, Brazil.  

In this modern age, lack of access to the Internet spells a loss of economic opportunity as well. A Brazilian nonprofit organization is building partnerships with radio stations to create telecenters which allows people to not only access the internet, but also to receive software and internet-training.

His paper, published in the Stanford Social Innovation Review, is available in pdf format here .