The best really thin socks for my feet are Injinji toe socks made of coolmax. They don't wear particularly well, but i can get at a least 30 solid days hiking per pair.

If I am running, I wear a single pair. If I am hiking I wear 2 pain (yes, one on top of the other). And in essentially the same shoe.

With one pair running (up to half marathon distance) no blisters in 5 years.
With two pair hiking/backpacking, up to 42 miles per day, no blisters in 5 years.

Paul - I was at Wal-Mart last night and this thread reminded me I wanted some ankle length socks. All WM's I have been to have these socks, they are Starter Dri-Star, they are 98% polyester 2% spandex. They have them in brown/tan, grey, and black and in ankle tab, low cut, ankle, and crew lengths. I think they run $5 for 3 pairs.

In the past couple months I have had several 8-10 mile days, one 15 mile day, then several 4-5 mile days plus probably a dozen 1-3 mile jogs in one of three pairs of the crew length socks like this I have and you really can't tell they have been used.

I am not a big believer of paying several times more for clothes, I think the majority of what you are paying for with clothing is the brand name. Especially when it comes to synthetic materials like polyester. Polyester is a really cheap fabric it has only recently been re-purposed and re-branded with all these flashy terms and brands.

The Dristar socks are too thick for me, I have a bunch of these and I cant wear them. They seem hotter and wick less than regular cotton for me, even in the office. Thin dress socks are not as bad but they also seem to wick poorly for me. the $5 Pearl Izumi cycling socks are a good balance of performance, durability and value. Somebody recently posted that foot care is very individual, I agree with that.