To answer a question, here's what I wear when it's -17F out and I'm running.
Patagonia Capilene 1 T-shirt and Crew
Patagonia R1 Hoody
GoLite Wisp or Ether windshirts
Black Diamond midweight gloves (Powerstretch)
Patagonia Capilene 1 boxer briefs
Patagonia Capilene 1 bottoms
Nike marathon shorts
SmartWool Expedition socks (heavy cushion)
Asics GT 2150 shoes
And when its warmer out, I tend to drop things in this order: Cap 1 Crew; R1 Hoody (swap for Crew; add fleece skullcap as necessary); Cap 1 Bottoms and briefs; windshirt; swap for lighter socks; Cap 1 Crew (leaving me in shorts, shirt and shoes/socks).
In sum, I own very few running-specific items. Lets see: running shoes, three handheld bottles, running hydration vest. The rest is just my hiking clothes put to a similar use.