As I said before, it is unlikely, but possible. A power surge has never happened to me, but a power failure has. What a mess it was. While none of the hardware appeared to be damaged, the operating system was a total disaster. I lost sound, graphics, and all windows settings were screwed up. Many files were corrupt as well. I had to reformat the hard drive and start fresh.
How can a power surge be possible? Well, have you ever noticed how the lights dim when the air conditioner turns on? What do you think happens when it turns off? There is a sudden increase in power flowing through the house. It lasts less than a second, but is noticeable. This is avoidable with a surge protector. Besides surges, static electricity can cause havoc on hardware when you are working on the inside of the computer. It is always wise to ground yourself before touching anything. For more on power surges and protectors:
http://computer.howstuffworks.com/surge-protector.htm