I'm going to be sending my PBG4 12" off to Apple to have the combo drive replaced. The odd thing is that the AppleCare tech I spoke to said that Apple might decide they need to wipe my hard drive and that it would cost $50 for them to back it up for me. Why the heck would they need to erase my hard drive to replace the optical drive?? Anyway, I'm not paying them to do it. So, I'm interested in suggestions on what all I should be backing up (including stuff like bookmarks, my Mail, etc.) and where to find those files. Thanks!