small batch water purification (hiking, etc.)

[MountainDon]

FYI, I ran across this UV light purification system. Great for hiking and the like where there is locally available water, but of unknown purity.

www.steripen.com

some advantages over the Katadyn type; certain disadvantages too (batteries, 4 AA, but can be NiMH for 180 x 16 oz. treatments) $100   Oh, and the water has to be clear before use so you still may need a filter to remove visible dirt.

[Amanda_931]

Yep.  Bacteria have to be hit by the light to get zapped.