I have some really small kittens for this time of year so I hung a 60 watt bulb in a cage with some blankets for them. I normally don't give the cats anything but being so small I don't want them to get chilled too bad. Esspecially my runt Boots, he's adorable but so tiny! Also cats love to sleep in straw! I'm sure if you gave them some straw most of them would snuggle right into it.