Grant,
I have a similar situation to yours, and have found myself thinking along those lines, myself. When the power goes out for over a day (happens once every 2 years or so), it's to get water that I'm forced to leave the house. So far this hasn't happened in winter, but it's only a matter of time... (I live 1/2 hour away from Calgary, by the way. My grandparents, in Halifax, lost several trees to Juan, themselves.)
I like building windmills, but I don't see that as a reliable way to backup my power. Now when I'm just starting out, that is.
The simplest solution I can think of is an "uninterruptible power supply". It charges a battery and keeps it topped up. When the power goes out, it goes into inverter mode and powers AC devices off of the battery until main power is restored. Simple consumer devices are designed to keep your computer going - you plug directly into them. Other types can be wired into your well pump's wires. This could be expensive, as I'm talking about an "industrial" type of power supply that businesses use to keep computers, refrigerators, security systems, etc. running.
The next simplest solution, and just as expensive, is a portable generator. My in-laws, who live near Montreal, installed one after the Ice Storm. They wired it into the house, on lines rated for 40 Amps or so, to a separate bank of outlets. When the power went off, they shut off the house's main breaker, fired up the gen, and plugged the fridge and some lights into the bank of outlets. If they'd been more ambitious, they could have patched this into the house's main circuitry, but that would require some serious interlocks on the ON switches to prevent things from blowing each other up.
Since you want "just one", you might look around town for businesses, fire stations, hospitals, etc. that are changing out their back-up power equipment.