While surfing the net this morning, I came across this url: http://www.demobags.com/. Seems like a good product, just only comes in one size 25" x 40" - not good for a poncho or related tasks. Having a couple of them would act as a good ground sheet and aid in shelter waterproofing and other tasks (like a strong bag to waterproof a backpack, etc).

What do you think?
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"One should not increase, beyond what is necessary, the number of entities required to explain anything"
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