Post offices in the northern state of Himachal Pradesh will take a customer's handwritten letter and computer scan it. Then the letter can be e-mailed to remote, high-altitude post-offices in this Himalayan region.
From there, the e-mails are printed out and then taken by hand to their destinations - many of which are located in almost inaccessible mountain areas such as the Lahaul, Spiti, Kinnaur and Pangi valleys.
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.