A spike buster is a elctronic device which takes in the sudden surge in power and doesn't allow it to get transmitted to the elctrical/electronic equipmrnt. They are of various variety, cpability and prices, from the simple blow fuze type to sophisticated circuits. Voltage stabilizers, UPS, CVTs and spike busters are some devices to ensure your devices are safe and not disturbed. For home PC a voltage stabilizer is not a must and neither is a spike buster. A simple UPS or CVT is enough. Ofcourse it depends how deep is your pocket then you can go for mutiple protection.