I sometimes try to
kill -9 Finder.app when it's misbehaving and I'm in a Terminal. This normally works but every once in awhile it leaves behind the pid, even when run with
sudo, and the COMMAND portion of the output changes to (Finder).
Interestingly enough, this process only appears in the output of ps, not in Activity Monitor.app. No idea how to explain that.
At that point, I'm in for a reboot given my current knowledge, but I don't understand why. Can anyone explain what's happening and maybe how I can restart Finder without rebooting?
EDIT: I will note that once I'm in this state, I can usually attempt to go through the regular ⌘⌥⎋ method and Finder.app will be there. Once I've force quit it though, the name disappears forever from the Force Quit dialog and the zombie pid sticks around anyway.
I'll also note that Finder.app is treated specially in that dialog, where the button text turns from Force Quit to Relaunch, so perhaps that shows that OS X treats killing the Finder as special?