One person advertised her Etsy shop, where she sells very pretty devices made of chains, jump rings and beads (it's here if you want to see them.) You put the first ring on your needle. When you get to it again, you slip the needle into the next ring in line. When you finish the chain, you've gone ten rows and you use a ring of seed beads to move down a row of ten beads. As I said, it's pretty and elegant, and clearly a fair bit of work. These devices are over fifteen dollars, and the ones for sock knitting (smaller rings and an extra length of beaded chain for Eye of Partridge heels) are even more. I don't think they're overpriced for such an elegant device.
Yesterday, I reached the heel flap on the current sock. This is the one part of a sock where I use a row counter. And I wondered if I could make something myself that would work as well.
I have small brass jump rings. I have several colors of small stitch markers, including both a white and a black set of rubber stitch markers. I made a chain of eight - four jumprings, two black markers and two white ones. The colors alternate and the chain begins with a brass ring and ends with a white one. (Most of my socks have stitch counts of multiples of eight. My heels are one half the stitch count in length, and when I make heels, I count each knit/purl repeat as one. So a chain of eight works perfectly.) I went through the chain twice, giving me the number of rows I needed. Least stressy heel flap ever.
And then I realized I can use the same chain to keep track of the heel stitch I was working in the round - a brass ring would mean k1sl1, a rubber one would mean just knit. I'm not counting rows here, and I can look to see which I'm doing, but this just makes life easier.