I was buying birthday cards at a local dollar store and ran across a 10 pack of synthetic/cotton blend socks for $3. I noticed they were pretty thin and ended up buying them with intent to try for working out. I have to say they're pretty nice for running. I'd spend the bucks on some real running socks if I were doing more than five miles but for the money I'm happy.
PSA: with no name, or brand, or anything else. Just go to the dollar store and buy whatever shit they have