I had to string out my inverter again this afternoon, luckily I was home for lunch when the power dipped, it was out about 90 mins. I have a 150 watt inverter that is just enough to run my return and power heads through a UPS (ups isnt strong enough to run the return on its own and the inverter struggles so they help each other.). I really need to get a dedicated backup that is large enough and a controller or something that'll email/txt me.
But anyway, in a pinch, a trip to autozone/walmart for a large enough inverter may be as good as a generator in most cases, just remember to start the car every now and then to top off the battery!