I have ridden in weather down to about 10° F (about -12° C for you Canadians). I wear similar clothing to Cycling@42. For my feet, I wear thick SmartWool socks in my regular mountain bike shoes and cover with 2 sets of neoprene booties. My feet stay relatively warm, though the farthest I've ridden at that temperature is about 20 miles. For my hands, the Pearl Izumi AmFib lobster claw gloves (see www.pearlizumi.com and navigate to "store" then "accessories" then "gloves") are the first ones that I have found that really keep my hands warm. In fact I can't wear these gloves if it is ABOVE freezing because my hands get too hot. If it is also snowing, I have a set of lobster claw GoreTex rain mitts (uninsulated), made by Outdoor Research (see www.outdoorresearch.com and navigate to "handwear" and then "waterproof" handwear), that will fit over the insulated Pearl Izumi lobster claw gloves. (The lobster claw style gloves have only 3 segments--thumb, forefinger+middle finger, and ring+little finger. They keep your hands warmer like mittens because each individual finger isn't exposed to the elements, but they let you control the bike by having the split in between the middle and ring fingers)