The Most Powerful Keyboard Shortcuts On Your Mac
Many keyboard shortcuts are frivolous and easy to forget because you can usually do the same thing with your mouse. There are some however, that you should be careful not to press, unless you know what they’ll do…
ctrl+shift+eject: turn of displays (make all screens go dark)
cmd+option+eject: quick sleep (*not* safe sleep… great for stowing your laptop quickly when you have to move suddenly)
cmd+ctrl+eject: normal restart
cmd+ctrl+power: force restart
Oh, and a couple bonus keyboard shortcuts:
Option + one of the Brightness buttons: Takes you to the Displays pane in System Preferences.
Option + one of the Volume buttons: Takes you to the Sound preference pane.