The airplane departed off the left side of the runway after encountering a wind gust during landing rollout. The nose gear strut collapsed when it impacted a runway light during the runway excursion. The engine firewall, elevator, and right wing were substantially damaged. The pilot reported that there were no pre-impact mechanical malfunctions or failures that would have precluded normal operation of the airplane. A local weather station reported that the prevailing wind was out of the south at 8 knots, with no gusts.