I just finished the first sock from some Luna Park 100% Merino wool fingering yarn given to me by my lovely and talented daughter-in-law. Since the yarn is 100% wool, I wanted to reinforce the heel and toe with nylon for added strength. I used Wooly Nylon serger thread which I just knit in along with the yarn. I used white, and it disappeared nearly completely into the yarn, even the brightly colored stripes. The serger thread was recommended to me by a fellow knitter, who didn't like the looks of the reinforcing yarns available in yarn shops. We'll see how it works.
I got the laddered rib pattern on the leg part and along the top of the foot by doing a knit 2, purl 2 rib and inserting a purl row when the color changed. I think it gives the sock a very festive look.
I did the knitting mostly in the car as we drove to McCall, Idaho for a few days of cross country skiing and snowshoeing. The snow was great, the weather sunny, company good - what more could you ask for?