I've been wearing these with heavy wool socks. So far so good. Temps in the 40s.

Pearl Izumi CalienToes here at TE for $19.99
http://www.teamestrogen.com/products.asp?pID=10526

Soon I'll be breaking out the shoe covers:

http://www.terrybicycles.com/detail....s&item_no=1417

They come in neoprene or windblock styles. I have the neoprene and they worked nicely when I was riding in the rain in Europe in October. But now seeing the windblock style.... I sort of wish I had those instead. Neoprene ought to be ok in the cold and wind as long as they don't get wet.

Martha