About once or twice a week I have a problem where the Finder dies. I think this is what happens, at least. I'll try to describe it. I'll be in Firefox or some other app with Thunderbird and iTunes running in the backround. I'll try to Apple-Tab and I'll notice nothing happens. I'll try to Force Quit and the menu comes up but there's nothing in it. Not even the Finder. I'll then become stuck in the application I have in the foreground. No amount of clicking or praying can switch the application. I can't Apple-Q and the menu bar goes dead as does the dock. I have to power-reset.
Why does this happen? How can I stop it?