Jigsaw blade... do you really mean a thin jigsaw blade, or a sabre saw blade?

Space blanket: formed into a bowl on the ground, it can be used to catch rainwater or dew. With one edge secured to a line with split twigs, you can drape the bottom into a container and catch even more rainwater. Cut a piece off and line your hat with it for more heat retention. Make a poncho with some duct tape.

Sue