After seeing this post, I was inspired to add up my own mileage. It was easy since I have a lot of multiple colorways of the same yarns, so for a lot of them I just had to multiply. I have 9539 yards, or 5.42 miles of sock yarn. That's not counting what's on the needles, or the little bits leftover from socks I've knit, unless it's both a substantial and an estimatable bit.
Wow. So should I join the marathon?