Can my laptop turn itself on after I've shut it down? I have a MacBook air, practically new, no problems until now.
I usually just close the lid and the computer shuts itself down instead of entering sleep mode.
Friday night, I shut my laptop down properly and didn't turn it on until this Monday afternoon.
Except I didn't turn it on - it was already on.
It was on, and very hot, and had a flashing file icon with a question mark.

So my question is
How could my laptop turn itself on, heat up, and fry my hard drive?
At one time, I used to run a couple applications that would inhibit my iMac from going to sleep.  So, if you have something running in the background that stops your mac from sleeping, that would be a candidate.  If it woke up, you may have a backup while plugged in turned on.  That does wake the Mac while it does that trick.

Now as for frying your HD?  Well, who knows.  Fried HDs do happen, and I suppose it could happen while a laptop is shutting down, which would answer both questions.  I did recently replace a HD on an older laptop.