This morning we encountered a MacBook that was not just dead, it was super-dead. It wouldn’t come on, even holding down the power button for ten seconds wasn’t sufficient to kill it and get it to start back up.
So I learned all new keystrokes to press to get out of this kind of situation that I’ve never encountered before:
Reset the SMC (http://support.apple.com/kb/HT3964)
Hold down the Shift + Control + Option keys (all on the left hand side of the built in keyboard) + the power button
Release and then hit the power button again
Reset the NVRAM / PRAM (http://support.apple.com/kb/ht1379)
Command + Option + P + R with the machine powered on
It took the last one to get the machine back to a working state, something I’ve never seen happen with a Mac before, but if I ever see it again, I’ll know what to do.