I recently posted about some bizarre behavior on my Mac Pro (icons disappearing, programs needing reinstalled, etc). This morning I started my MacBook Pro, and now it's being flakey! I last used this MBP at work Friday. It was shut down and remained so all weekend. When I fired it up today, it seemed to take an extra long time booting. When OS X finally appeared, I noticed that the desktop pics had reverted back to the blue default image on both the MBP screen and a separate monitor I have hooked up to it. My color calibration schemes were gone for both. The dock was back at in its default state. My Mighty Mouse was reset back to its default behaviors. Things like Finder Sidebar were back to their original configuration. My documents appear to be in place, as do my apps. However, when I manually started up Quicksilver, I noticed that it went through its setup routine as it does when first installed. Starting apps like iTunes brings up the EULA type screen like when it's updated. Palettes in Microsoft Office programs are reset. The system is acting as though there were a massive disappearance/replacement of preference files. I don't have my OS X install discs with me to verify the disk. Repairing permissions reports nothing out of the ordinary. Where else should I be looking? Anyone have any ideas?