Some surge protectors offer guarantees of a certain amount. I belive APC sells surge protectors with $10,000 damage guarantee if it fails. I don't think surge protectors really do much. The ultimate saftey can only be had from a UPS (uninterruptable power supply, a.k.a. back-up battery,) that will help reduce voltage spikes and drops that effects the computer.
-----------------------
oh, its a nice day. TO EAT CHILDREN!!!