Buffs, Snoods, and Neck Things: The Geometry of Keeping One Bit Warm

That tubular fabric thing you pull over your neck can also go on your head, your face, or configure itself into several other positions depending on how committed you are to solving problems with a single piece of stretchy cloth. Whether any given tube will actually keep you warm, block the wind, let your skin breathe or shield you from the sun depends entirely on what it's made of and how it's put together—not on the fact that it's shaped like a tube.