For all you audio and video-philes out there, look at this: www.audiolinesource.com
It really is an incredible little powerblock. In actuality all it is is a HUGE inductor wired in parallel with the power line. Any spikes are culled into the magnetic field, as are temporary dips in power filled by power remaining in the same field. I did some work for one of the owners of the company, and he showed me what a difference it could make. If I had the cash, I'd have one. Alas, I don't.