I use FileVault to encrypt the contents of my home folder. In the case of my laptop being stolen or lost, the new user should therefore be unable (or find it extremely hard at least) to access my work and personal confidential data.
FileVault is very powerful, but it has a downside: FileVault loses some of my file associations and related preferences each time I log out, restart, or shutdown. For example, my preferred browser is Firefox, not Safari. Therefore, every time I log in, I have to reset the Firefox to be my 'Default web browser' in the Safari settings dialog.
Since OS X v10.4, this behaviour has been driving me to distraction. This is a known problem, and has been widely reported by FileVault users (see this hint, for instance). I was hoping that this would have been fixed with 10.6.2, but alas, the problem continues. So I set out to solve it.
Under OS X, file associations are saved on a per-user basis (as opposed to some other OSes), in a Property List (plist) file named com.apple.LaunchServices.plist, which is stored in your user's Library » Preferences folder. This file appears to be rebuilt upon each login, so any file association settings created during a session are effectively lost the next time you log out and back in again.
However, if you don't mind all local users sharing the same default associations as yours, you can copy this file (after you've applied the right associations, of course) to the /Library/Preferences directory. You can do this by copying or moving the file in the Finder, or if you prefer the command line (Terminal), with:
cp ~/Library/Preferences/com.apple.LaunchServices.plist /Library/Preferences/Upon a restart, you should now notice your settings are now working properly. Interestingly, it appears the local user plist file is regenerated by copying the contents (if any) from the /Library/Preferences/ directory. It is a simple workaround, but it seems to do the job. Apologies if you've seen this before, but I haven't found this information anywhere else.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20091112095601678