With winter hitting us I was wondering about a heated kitty bed of some kind. Has anyone ever used one? Any pros or cons on using one? My patio doors where my kitties usually like to hang out to watch the birds and squirrels give off so much of a draft that they are starting to stay away from their 'favorite' spot. I feel bad because they love watching the birds so much. Any suggestions out there or websites that people know of with a good product of this kind?