Topic: gear comments
Yes, I'm talking those ultra-thin mylar sheets that are packed down into a cigarette-sized bundle in their package but that mere mortals can't fold smaller than a paperback book!
I have one in my kit, partially based on so many kit-lists having them. I've never tried to sleep under one.I have, however, used it as a signal panel. We were on a large pipeline right-of-way (at least four large-diameter lines) testing out radios over roughly a two-mile distance. Team One was dropped off on top of a hill and Team Two proceeded to the next road crossing. From two miles away, Team Two could see us when we moved around and let ourselves be outlined against the sky. Once we relocated forward, that problem vanished.
Since I had my patrol-pack with us, I decided to try out the blanket! We unfurled the flimsy mylar and held it up by its corners. With a light breeze at our backs, it billowed out like a sail. The radio immediately popped to life. "I don't know what you just did, but I can sure see it!"