There isn't, but there is something close- turkey bags. <img src="/images/graemlins/smile.gif" alt="" />

Mark them in quart increments before you pack them, and there isn't a lot of guessing as to how many you need when you have to add water tablets. Two of those and a couple of twist ties take up about as much space as two condoms.
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-IronRaven

When a man dare not speak without malice for fear of giving insult, that is when truth starts to die. Truth is the truest freedom.