It was fairly cold this morning (-8C). Finally I figured out how to keep the toes warm enough during my long commute (before, even the Sorel winter boots with warm wool socks were not enough). I cut off the toe part of smartwool socks and used it as a
slip-on cover for the toes, over the normal wool socks (see the picture). Actually,
I had it just on my left foot; my right foot was without the additional cover. The difference was very noticeable. BTW, at least in my case wiggling the toes is not
enough; also wiggling the whole foot (giving the ankle some exercise) helps.