Tvpicks.net will tell you if there is anything good on tonight without having to slog through all of the crap in the TV Guide. As an added bonus, she usually has a cool quote from Homicide or Buffy at the bottom.
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.