Haha I saw this post just as I was whinging about how wet and cold my feet feel! Yes, reynauds is a common cause. I have some scarring on my feet from when I put them under a radiator, and didn't realize they were touching because they were numb from cold. I am the oposite, I can't sleep WITHOUT socks, but they don't always help. Heating pads are good, and running them under lukewarm water. Not hot water, cuz that'll just burn. Do your hands/fingers get unreasonably cold, too?