Designer Rachel Coopey is best known for her beautiful sock patterns. She now has a sock yarn of her very own; Socks Yeah is a blend of fine superwash Merino (museling free) with the added benefit of nylon which makes for the perfect yarn for knitting socks.
It's finer than a 4ply, more a light fingering weight and has a wonderful twist to the plied fibres which makes for a great stitch definition. It's a soft yarn so you might not want to limit yourself to socks, why not use for shawls, hats and other smaller projects. If you crochet you'll be interested in The Crochet Project's book, Crochet Yeah!
Socks Yeah comes in 30 colours that coordinate beautifully together. Smaller 50g skeins mean Socks Yeah is great for stripes, colourwork, contrast heels and toes on socks.