Natural gas lines that run by your house? I've never used NG. My aunt and uncle use it for 'logs' in their fireplace. My uncle says he wouldn't take anything for those logs, either.
Do you still have heat when the power is out? My furnace is oil-fired, but no electricity to run the forced air means no heat. Luckily I have a fireplace for burning wood if I'm too long w/out heat, though I hesitate to use it because the firebox needs repointing around some of the bricks.
I'm pretty sure I have natural gas - my water heater is heated by gas as well as my oven.