The other "standard" recommendations, in addition to the ones Sean made, are to replace your wall plugs with hospital grade units (I didn't find this made much difference in my system, but other people swear by them), and using a line conditioner power strip, such as Monster Power's HTS2000 (I have two of these, and they DO make a difference in my system). The hospital-grade wall plugs can be purchased for around $25-30 each, and the HTS 2000 units can often be bought at discount prices for about $140-150.