Ok, need some help. My mid 2010 MBP with current Mountain Lion (10.8.1) has been randomly freezing with the spinning ball. One trip to the Genius bar resulted in temporary help after repairing the permissions, killing some background processes that ran on start-up and other clean-up/disk repair tasks. Later that day, the problem returned, and so did I to a different Genius bar. There, they kept the machine for a couple of days to observe, reinstalled 10.8.1 and "fixed some memory allocation issues." Back at it. Still getting the beach ball freezes. I can't replicate the circumstances as it is somewhat random. Seems to kick in when going between browser (both firefox and safari) and MS Office apps and a save to disk...but again, it's random and not repeatable on demand. I just had it happen loading a Web page and nothing else. I also uninstalled and reinstalled Office, although it never asked me for my product key and seemed to remember the old one. The .plist file for the product key doesn't seem to be in /library/permissions as it should, nor is there a /library/microsoft folder. I called the store back to ask what to do next; no one got back to me today, so in an effort to avoid the definition of insanity and go back, thought I'd see what you all had to say.