From this article
http://science.howstuffworks.com/nature/natural-disasters/lightning.htm
that explains lightning in great detail:
Surge protectors won't save your electronics (TV, VCR, PC) if lightning strikes your power line. Surge protectors provide protection for power surges in the line from the power company, but not for lightning. To really guard against strike damage, you need a lightning arrester. The arrester uses a gas-filled gap that acts as an open circuit to low potentials, but becomes ionized and conducts at very high potentials. If the lightning hits the line you are protecting, the gas gap will conduct the current safely to ground.
More on arresters here: http://en.wikipedia.org/wiki/Lightning_arrester