Tangent: I once received tips on doing field work in Siberia from someone who had, and one of them was "use a Nalgene [well, Soviet equivalent] to piss in your

Tangent: I once received tips on doing field work in Siberia from someone who had, and one of them was "use a Nalgene [well, Soviet equivalent] to piss in your bivy sack — you went to all the trouble to heat up that urine, don't let it go to waste rapidly equilibrating with the outside environment".