Not to be confused with a Smash Book, a "smoosh book" is, as Donna Downey says, a book that you can smoosh leftover paint, sprays etc in for later use. I love looking through my smoosh book when I'm looking to get started on another journal page and this is one of my favourite results:
So all of the colours/drips were previously smooshed and all I added was the black stencil-work! Isn't amazing how the "tears" lined up with the face stencil?? A total fluke!!
"Smoosh Book: - Dylusions Sm. Journal