I learned about Spirit Slates at the end last month, and I guess it is a good thing I stumbled upon the ad first, or I would have had no clue what I was looking at when I found this:
It is just a little bigger than 4x6. I can see the chalk markings of where someone had once used it. The little secret take-away panel comes out a lot easier than I thought it would.
Between the panels, I found this typed description: