I've never experienced a HD crash before, but I've always been interested in finding out about it. Just wanted to know: 1. What causes it? 2. The chances of it happening? 3. Can the data be recovered, or at least some of it? 4. Are there any warning signs that could be pointing to a crash? I'm asking these questions primarily focusing on a MacBook Pro. (read my signature) Are there different chances with my model of this Mac? I do have 2 External HDs that I use. A Western Digital 120GB HD and a Maxtor 500GB HD with a 5 Year warranty.