Uncle Roger, I could've swore I used that on a fill-in once upon a time... Weird...
Hmmm, nothing comes up in a search of any of these Complete This Phrase / Fill In The Blank(s) or even the Caption This! boards.
(Or maybe that was just a dream.)
Ha! Or maybe you meant to use it as a fill in but you got distracted at the time (by a phone call, someone coming into the room, etc.) and forgot - or perhaps you meant to go back to use it but forgot.