Defeet Wool Blaze - best socks ever. I wear them year-round - wash no more than once a week, and they never smell.

Followed closely by some Icebreaker mid-weight socks. Don't remember the exact model.

In a thinner sock, I really like the Craft Pro-warm, but since I prefer slightly thicker socks on the bike, the Craft get worn primarily off the bike. I have a couple of other thin socks that never get worn. Many of which are supposed to be winter socks.