I was reading on how to keep your hedgie worm during winter travel. I keep her in my house, and don't travel much to buy one of the warmer disks too spend $40+. However, I was wondering if anyone knew how to make something similar. I have rabbits I would like to use something warm. I have read a sock and rice? Is rice a good choice? Should I use something else? Im sure my hedgie would love one if we ever needed to go anywhere.