I spend a stupid amount of time thinking about warmth when it’s cold outside. I detest the cold… And one of my favorite ways to stay warm is the Rib-Pile material that Relwen uses on a number of different items. It’s sort of like your typical waffle under layer, but it’s thicker and more substantial. Also, it has some stretch to it… but, more importantly, it has a good memory and never stretches past the point of no return.
Highly recommended.
Details here.