Fleece and good under garment for your torso (I have Marmot, HH and Northface). It has to be COLD for me to consider long underwear bottoms.
I like a fleece vest with windstopper, and layer accordingly over/under.
I generally wear a base layer and Mountain Hardwear wind stopper vest incase I need to strip down and get moving. I wear a Patagonia Nano over that for insulation and a Mountain Hardwear technical softshell if there is wind and moisture. A neck gator and windproof fleece beanie keep me snug.
Like SH said, it has to be COLD before I wear anything on my legs.
