I am a sock knitter. I knit about 15 pairs/year, and sometimes I look around a room and realize that everyone is wearing a pair of socks that I made, and I think that's fun.
Knitting is definitely a hobby, not a cost saving activity. People always say, "But you can buy socks at WalMart!" and that is absolutely true. I knit because I enjoy it, and it's easily portable, and I'm a fidgety person.
I do like heavy bed socks and thick boot socks, but for everyday wear, you want actual sock yarn, with about 25% nylon content, and you want to knit them to a tight gauge, probably on size 1 needles. There are some pretty fancy sock yarns out there and they are lovely, but you will not get the wear from them that you will from Regia or Opal or KnitPicks commercial sock yarn. Regia and Opal come with 10 year guarantees!
I wash our many pairs of wool socks in the washing machine, and hang them to dry, so not really any special care. And I don't wear socks in the summer, but have been told that wool can be quite comfortable even then. There are also some cotton sock yarns - I've made some yoga socks out of it.