You know those little fur hats from Russia
? The big, black/grey/steel blue
things that look like little furry animals sitting on your head? Well the correct term for them is not
Russia fur hat, it is...drumroll please...USHANKA!
In all seriousness, these things really do keep you warm. I bought one through a catalog called the Sovietski Collection, a Red Army surplus hat, straight from the former Soviet Union, hammer and sickle pin included. And they really keep you warm. I could go out in -15F weather with the blasted thing on and my wool coat (also Red Army surplus...hey, they needed money!) and feel like it's a balmy 30F+...I put it on Christmas Day in 2000 (Tennessee had a freak warm winter...50F high instead of 30-40F highs) and literaly broke into a heavy sweat.
Ushankas. Don't visit Siberia without 'em.