Sleep Bulletin Boarding?

Ok, so weird story...  You know that stray push pin that seems to have fallen into the black abyss of nowhereland?  Well, in the middle of the night last night, after a long day of putting up bulletin boards, the aforementioned push pin turned up in my hand whilst I was sleeping.  Not stabbing my hand, but snuggled up in my hand like some treasured object.  How it got there?  I have no idea... My shirt?  My hair?  Baffles me.  Guess it's one of the mysteries of being a teacher...