What about insulating the air filter canister as per Landtank a while ago? I've been thinking of this myself, but I'm not sure what to use. Ideally something with a reflective surface so it "bounces" the heat off the canister. I'll probably wait until the spring though, as I'm not sure if the engine will like really cold (0*F) winter air without the preheat effect (I have no basis for this idea, but then again, when do I ever?)
So, yeah, what about insulating the canister?