Indian scientists from Amity University have developed a curious, portable water-purifying system.
It looks like a teabag, but instead of tea it contains silver-imbedded pebbles.
According to the developers, when placed in water, the purifier provides about 99% decontamination of microbes.
Silver teabags are expected to remain effective for up to around 120-125 uses within a six-month period and can clean nearly 1,000 liters of water. The device does not use any electricity nor other energy source.
Scientists continue finding new and innovative uses for silver.
This one could become important in areas with limited or no potable water.
http://www.silverinstitute.org/site/.../SNOct2012.pdf
Article and picture on lower right of pdf page.