No Sweat Socks
From No Sheep For You:
The No Sweat Socks are mostly unribbed for two good reasons. The first is that the yarn - a marvelous blend of soy and polypropylene - has a god degree of elasticity so will stretch to fit and bounce back on its own. The second is that the veriegated colorway looks better in plain old stockinette stitch than in a rib pattern (but you do need a little bit of ribbing at the top to help the sock stay up, and to stop the top from curling). The polypropylene - often found in sports and outdoor gear - wicks moisture away from the skin, making it ideal for socks.
Top-down construction with a heel flap on double pointed needles.