Remedial massage has been a lifesaver for me - along with warm baths, heat packs, and the odd panadol when it gets really bad.

Also, wearing really comfy, supportive shoes, and watching my posture - I keep finding I am swaying my back, with the belly thrust forwards. When I remember to suck in my bellybutton towards my spine, and lift up through my back and neck, this really helps take the weight and strain off my lower back.