I'm a huge fan of a good pair of socks. They are one of few proper hand crafted fashion items that are still within price reach of most people.
Forget your M&S etc, a proper fair of over the calf, hand linked toe, cotton or wool socks is the only choice for a true gent
This is historically because the last thing you should ever reveal when sitting down, is a flash of leg. Something that happens far too often with ordinary high street socks! Added to this the fact that over the calf socks stay put all day and aren't circling round your ankle like an MP's pants and with hand linked toes offer almost unrivalled comfort.
I go with a few brands.
-gammarelli - these guys make the socks for the Vatican, amazing pure Marino wool items of sheer comfort. Not so many colour choices (red, black and purple obviously) but so very well made
- Mazarin - very French, delicate, light and great in the summer,mostly cottons and very fine gauge at that. Not long lasting though as a result. With frequent use, expect about a year out of them
- bresciani - very premium, probably the best made out of this first three. Very interesting designs and very comfortable. Also very long lasting.
On the more affordable side:
-pantherella - uk made, fairly well constructed if not particularly fine or precise. They are good for every day wear.
-falke- as above just decent full length socks made from long isle cotton
And at the budget end, but a nice new find for me.
- viccel - recently found these chaps, made in turkey, and yes, they aren't all that delicate or finely crafted, but they are comfortable. Look superb, a very solid and sturdy and the colours are vivid and long lasting. At nearer £6 a pair they are by far the cheapest I have, but are becoming my favourites for every day wear on comfort grounds.
Hope this helps someone! Socks are a delight when done well and give a feeling of luxury that's hard to beat