A couple years ago, TimS and AndyD convinced me that I need to try wool socks. It sounds silly, but it was a life-changing discussion. Since that first purchase, I have worn wool socks almost exclusively. In the winter they keep my feet warm and in the summer they keep my feet from getting sweaty and wet. They’re brilliant! You can get them fairly cheaply in big bundles at Costco. Unfortunately they only sell them during the winter so I like to stock up and have a few bundles in the closet in case I wear some out.