Here's what I was looking at when I get some cash to buy a generator. Looks like a good idea, at least to me it does. This way you don't have to worry about storing gasoline and/or refilling it. I can't think of any time I've had an interruption in my natural gas service.
http://www.propane-generators.com/
You can use these conversion kits to run off either natural gas or propane.
Anyone out there have any experience retro-fitting something like this?