Its happened twice today. I have my MBP on an icurve, and then I unplug the magsafe, and close the MBP to take it downstairs. about 5 seconds later it makes the same noise as it does when its woken from sleep mode, and it does that twice and then you hear the start up tone (all this happens when its shut) and then it re-starts. Very strange. Can someone else try this with theirs, to see if it does it. Unplug it and as soon as you unplug it, shut it straight away and see if it re-starts.