Low-tech Inventions That Help Change Lives
I read an article some time ago which outlined a very low-tech way to help purify water in countries with high incidences of Malaria, Dysentery, etc. By painting the surface of huts/housing flat black and placing clear plastic water bottles on them for a few hours. The sun & UV help to kill off most parasites and biological pathogens quite effectively and at a price much cheaper than other filtration solutions. Nice low-tech solution which is cheap, effective, and requires no special equipment.