Have you gotten into the foam roller
game at all? They work wonders. I have pulled an erector in my back twice during the last 5 years, and I came back from it much faster the second time when I learned about foam rollers.
You just roll on the damn thing like a log. Crazy, right? It sounds like pseudoscience, but I can say that ample anecdotal evidence backs their use. My powerlifting crew has several, and we've all used them from time to time with great results. Their most common use is to work out lactic acid and otherwise warm up tight muscle groups in your back, but several of us have had great success using them to help rehab tweaked back muscles.
Trust me. Hit one of these things for 2-3 minutes after a lower body workout (squats, deadlifts, good mornings, whatever) and tell me that you don't feel great.
EDIT: I should note that it won't make the pain disappear entirely, but I expect that it would go a long way towards loosening you up and easing the pain.