As is probably the case for many of you, I'm going to be selling my ~4.5 year old macbook pro and buying a new MBP. So, of course, I'm going to wipe the drive. But I've heard stories that even if you wipe the drive normally (e.g., reformatting), some people will buy the computer and try to steal data by restoring it. What's the best way to prevent this from happening? Will a basic reformat do it? And, how would/should I go about reformatting my computer's main drive anyway? Just do it in disk utility like with an external HD? Thanks.