Another recommendation for the cold weather:

http://www.rei.com/product/770632

I thought I'd give these a go -- being one of those who gets cold feet rather easily. They are a dream. The bonus---your calves stay extra toasty. Wish they were TIGHTS, actually, or came up to the top of my thighs.

They aren't too bulky so a chemical heat warmer toasts your toes nicely. Also, there's room in your shoe so the heat can circulate.