You didn't say whether it was upper back or lower back pain and I know that cjmomma mentioned hip pain. I'd read a response a while back from AliKat and she recommended this special cushion - the one I have is called a Gypsy Sit-Upon and I got it through Nancy's Notions. It mimics a balance ball and takes pressure of your pressure points - I used it for my Quilting Boot-Camp experience with my weekend long Judy Niemeyer machine piecing class and felt great at the end. It cost me about $30.