Sunbeam's Slumber Heat Therapeutic Pad is a torso sized heating pad safe to sleep on. Low heat means there is no danger of burns. When I went to bed with minor muscle pains they were gone when I woke up. You can sleep on it for nine hours before it will shut off!
Its hard to get used to the low heat compared to what you are used to in a normal heating pad, but this works. You wouldn't want it hotter or you would just be sweating it up. It relaxes your aching muscles and soothes them. My sister discovered the benefits of using it with her janitor job.