You all know that Mike C! is an advocate of "thinny-thin" socks. The new minimal shoes (not the toe-y ones) also do well with really thin socks. And if you're fording many streams, really thin socks help things dry quickly.
I haven't seen it posted anywhere, but cycling socks are great "thinny-thin" socks. Most are made of nylon, although wool is available (not quite as thin). The nylon ones come in a huge assortment of designs, colors and heights.
Just as an example of what's out there, here's a link to 8 pages of men's cycling socks:
(I have no connection with the company)
Cycling socks are widely available at cycling shops, and can often be found on sale on the web. And the nylon ones last forever!