If you're often away from home and concerned about power outages, then a company called iSocket Systems has you covered. It's created a product called the iSocket 3G — a power outlet that'll text you when the power goes out. It uses a small battery backup, a cellular radio, and a SIM card so that when it detects an interruption, the socket can stay powered long enough to alert you of the issue.
It's up to you to get the power back on
Of course, it's still up to you to handle the problem. The device is going to be most useful for people who have critical parts of their home that need to stay powered and are frequently at risk of an outage. iSocket has a handful of suggested uses: "shore power failure monitoring to marine applications, power monitoring of fridge/freezers or vaccine storage aggregates and monitoring of power during the cold season to avoid frozen pipes." I'm not sure how many people are storing vaccines at home, but it's understandable why you'd need to know immediately if the power failed. Just make sure you have a plan to get the power back on.
The iSocket 3G sells for $199. iSocket also sells a $9 temperature sensor that goes with it; it can get the device to text you if the surrounding environment gets too hot or too cold, which ties into the seasonal uses it describes. You'll also have to pay for the SIM card and any associated service. It's kind of pricy altogether, but that may not be a problem if you have critical components to protect.