I've just got my MBP after having the keyboard replaced under warranty. Because the Apple Store had no appts for over a week, I took it to an Apple Certified repair place and, when I left it two days ago, he asked for my system password. Having collected it I have just realised he could have installed anything on my computer - including mal or spyware. I realised this because when I opened my Mail app it opened on a random old email with a silly photo of me so they've obviously had a good look through it. I'm going to change ALL my passwords now to be safe (even though spyware will just tell them them all anyway) but is there anything I can do to check what they might have done?