The best socks EVER are SmartWool. MMmm. MMmm. MMmm.
I have 8 or 9 pair, and will never wear another now. Their new PhD model features what they call WOW technology - Wool on Wool. More wool now in areas where where there was nylon. The best, hands down. Not cheap, but they last for years and years.
www.smartwool.com