It's the time of year when power cuts caused by lightning strikes seem particularly common. Whatever the cause, the effect of a power cut can be costly - for example, food in fridges and freezers can spoil.

While a lot of equipment will automatically restart when power is restored, items with mains-powered clocks will need to be manually reset, and certain sets of gear may require that individual items must be powered up in a certain order for correct operation.

And sometimes the fluctuations in the power supply around an outage can damage the equipment.

If the owner or other responsible person is on the premises at the time, they can take appropriate action immediately. But what if the incident occurs out of hours, or at a remote location?

That's where iSocket comes in. Although it resembles a surge suppressor, it actually detects when a power outage has occurred and sends a warning SMS to up to 10 phone numbers.

While it works with any mobile operator's service, iSocket Systems recommends the use of low-cost mobile virtual networks with long expiry of recharges, or other tariffs that make sense for the expected number of SMSes per month.

The company specifically mentions Truphone, which charges 9c per SMS. But it's not clear from Truphone's site how long each prepaid recharge can last.

Another possibility is Virgin Mobile's long expiry option, which allows 19 SMSes to be sent in a six-month period for $15, or an unlimited number if the destination number is also on Virgin.

The list price of iSocket is $189, but the initial stock is being sold at $159 each, or two for $298.

The company offers a 30-day money-back guarantee and a two-year warranty.