Low-cost UPS ideal for home
Whether you believe in global warming or not, it does seem to be the case that power brown-outs are growing more common. The easiest way to manage that is a UPS or "Uninterrupted Power Supply", pretty much a chunky battery in a box that powers your gadgets either until the mains comes back on or to give you enough time shut the system down properly. Problem has traditionally been that they're pretty expensive; thankfully Ultra Products have decided to roll out a budget range.
A USB port means the unit can communicate with monitoring software, and a built-in alarm can warn you if it's overloaded or has a low-battery. A green mode and automatic charging cut-off means they're more environmentally friendly than, say, clubbing a seal. And better at powering your PC, too; in fact your PC and three other things, since they each have four outlets.
The four-model range starts at $49.99 for a 300VA, 150W unit, rising to $89.99 for a 850VA, 425W model. Wikipedia has some guidance on picking which voltage and wattage is suitable for you.