Look 'Ma, no Shell !

- Click Start/Turn Off Computer
- Press (and hold) Ctrl+Alt+Shift
- Click Cancel (in the Turn off computer dialog)

Oops! The Shell is gone. You'll tell me that it's even easier to kill explorer.exe using the Task Manager. Maybe, but my method gives you a couple of bonuses :

1. Explorer is cleanly shut down. Certainly less brutal than killing the process.
2. From Task Manager, File/Run : Explorer.exe → Explorer doesn't restart as the shell anymore. Quite fun (!) to use Task Manager as your task list. ;-)

If it's useful ? Well it was for me: I had a file stuck. I couldn't delete it inaymore even though the apps using it were shutdown. It appears the shell was locking it. Shutting it down saved me a reboot. (Trick found here)