Uninterruptable Power Supplies
Dear  [Lynn],
What you’re asking about is called an Uninterruptable Power Supply (UPS). You can get these at CompUSA and Computer Discount Warehouse (CDW), Radio Shack, and other computer hardware suppliers. However $80 for one sounds a bit low. The ones you’d get for that are probably bottom-of-the-line. Typically, the more you pay, the longer the unit can run your computer during a power outage. If the fluctuations are pretty short, then the cheaper units may be enough to protect her computer from the line voltage variations she’s observing.
Tom