Wholeheartedly agree with Richard wrt UPS/mains conditioners.
These days they are not expensive - APC IMHO are the best around.
You would be amazed at just how 'dirty' mains supplies can be at the best of times and PCs and the like can be very sensitive to spikes, surges, brownouts etc.
I have seen all manner of damage done to Computer equipment over the years caused by poor, unconditioned mains.
One particular example that comes to mind was a CISCO switch which kept blowing cards as it was in a bulding adjacent to a large water pumping station. All manner of mains interference when the pumps were switching in and out. A simple UPS solved the problem.
Plus you will still be able to surf when there is a power failure (for 30 mins or so at least) providing your ISP has UPS at it's local node - mine doesn't as I discovered last week !