the website below says this solar water disinfection device
which can be attached to a pet bottle will make the water
in the bottle potable with a few hours of exposure
using just the uv rays of the sunshine; no chemicals or electricity.
the site says it is going to test the device in odisha in a big way.
u can get the device called WADI for about 50 pounds now.
the ultimate price when distributed on a large scale will be
3D printing is not printing but manufacturing things
using a computer design automatically. well almost.
the site below gives details of a 3D printer which
can make things almost 6 inch in dimension.
the printer costs about 1000 usd . if any one has
first hand experience of using 3D printer please post
it here as guidance for intending users. i have no