For the Cold-Blooded

The SmartWool Midweight Long-Sleeve Zip-T. This top is described as a base layer thermal to wear skiing. I wear it everyday as a shirt...as an undershirt...as a sweatshirt. Made of 100% wool but not thick or scratchy. And it can go in the dryer!

Runs you $60-75.
Probably cheapest at the sporting goods store that decorates with taxidermy. Also available in men's.