This can be a can of worms.
I use a good surge protector($20~40) and then a battery backup UPS($80~100).
There is a lot of FUD out there. So much in fact that I did some research on the subject.
I'm a engineer at Chicago FM radio station, we are on the 10th floor of a downtown office building. I went to the shop turned on the oscilloscope and scoped the AC line. What did I see you ask??? I saw a nice and CLEAN 120VAC 60hz sine wave, I then pluged a B&D saber saw into the SAME outlet and TURNED it ON!!!! While watching the scope I saw NOTHING but the same 60hz sine wave. The floor below is the main computer room for a large corp. it is full of computers and the like. Now if your next door neighbor is a big factory you might have some interference.
Surge protection, YES! Battery backup if you have HDTV with a lamp, If you lose all power when the set is on the cooling fan will stop and the residual heat in the lamp can melt it! I have seen this happen. John