(Found in the comments of the digg post that shows the Amnesty International home shopping spoof of arms dealing. It's on the Lord of War DVD. That movie freaked me out. Way too real. I'd almost rather not know. I still think about that little girl with half an arm asking the white man if it will grow back.)
I have found it helpful to do the stretching exercises my physical therapist recommends. Do some core strengthening exercises, such as the ones highlighted at The Mayo Clinic. By keeping your core strong, your back won't put itself in a position to cause that sciatica pain you are having.