Ok, talk about pillows is a better descrption, but I couldn't resist :)
Every once in awhile I have back problems (really nerve pain) that are quickly alleviated when I change to a smaller pillow and by sitting with proper posture during the day. The, I get tired of sleeping on the tiny pillow, even if it doesn't make my neck crane in obscure ways, and I go back to the old big pillow. I can't help it, it's comfy! I'd love to solve the sciatica problem forever. Do buckwheat hull pillows work for you? What is a good source? Or is there something better out there? Or would doing something differently be better?