They are discussing pinball machines over at metafilter. That got me to thinking about how I had my own full pinball machine when I was a kid.
I really loved playing pinball and my parents were concerned about my safety, since the pinball arcades were full of unsavory characters. Their solution was to buy one for me. There was a little window on the backglass that showed the number of games left. We used to open the back, spin it up to 99 and go to town.
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.