switch it off first! (Thats Brains)
First rule of driving on the roads in Britain as I've see many a ar*e hole cut me up and almost wear my car as a mascot.
Anyway... there's this almighty crack, and a lot of sparks about an inch from my hand, then silence
Yes that does happen when you try and plug something in thats not designed to be "hot swappable".
Moral of the story: Lick your fingers before putting them into a plug socket to make sure it's turned off.