I try to avoid encouraging people to go out an buy green stuff which you don't really need. THat's not really green at all. So when I get excited enough about an eco-design to plug it, it's special.
Check these awesome leggings out. They help you stay warm when your thermostat is set in the low 60's, they're made out of bamboo, a sustainable natural fiber (microfleece is usually made from virgin petroleum; cotton requires a great deal more inputs than bamboo does). Plus bamboo is INCREDIBLY SOFT. And these are so pretty, too. Score, A+. They run big.
On sale at Norby's - from Detroit Lakes, MN. They know about cold weather there!