Do you wear underwear or knickers? I suppose your answer would depend on where you're from. Or maybe you're just one of those people that likes to pretend their European, so you spell things the English way, like "colour," or say "joie de vivre" a lot because it sounds cool. Whatever your flavor, knickers or underwear, they both have the same purpose: to cover your hiney.
London based Green Knickers boasts the tagline, "Fair Trade Organic Undies for Nice People." They bring hiney coveringness to a whole new level with feminine bows and sensual satin, all made with hemp and silk. And they've got a selection for the boys too.
For those not in the U.K., shipping across the pond isn't exactly eco. Offset your sin by not buying any clothes from the evil mass clothing conglomerates.