Since I was young, I've enjoyed the kind of books where an extremely close-up photograph is shown and you have to guess the larger object of which it is a part. Recently, when I was reading Look Closer with M, it struck me that it wouldn't be that difficult to make a book like that of my own using a digital camera.
I took a close-up and a regular distance photo of lots of familiar things from around the house (toys, appliances, etc) some hard, some easy. I printed them out and turned them into a little blank board book, but it would work just as well to leave them loose and use them like flashcards. M enjoyed the activity, and G actually guessed some of the pictures too!