Shelter halves...LOL. Never saw one after Basic. We spent our time living out of tracks/trucks or hootches in third world playgrounds. Screws always come in handy when building hootches...made a solar charger for a cheap 9.6v cordless drill, no use in breaking your wrist trying to drive a 3" deck screw into plywood.

Plywood? Oh, yeah...combat engineers would always drop a pile of cr*@ in front of us to use for overhead cover and the like. Depending on where we were at, the first thing we'd usually make was a bar....
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Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, a critter that can be killed but can't be tamed. --Robert A. Heinlein