You have my sympathy - it's bloody awful. I find it helps to lie on my back, shoulders flat to the floor, and then swinging one leg up and over the other to flex the spine and turn the pelvis while keeping the upper body flat.
Touch wood, I haven't had an attack for a while, which may be related to starting a new job which has meant a lot of lifting and hefting, strengthening the back muscles.
Smoking dope also helps, but the legality of such 'therapy' might be a problem where you live!