I often draw the characters of my stories, just so that I can understand what they look like in detail. My mind can only go so far when it comes to describing things out of the blue. But when it's drawn, I can definitely pinpoint the most important descriptions of the characters.
As @WintreKitty stated, A Series of Unfortunate Events had chapter illustrations that really helped move the story from simply imagination into exactly where the author wanted it. On my own, I would've pictured the children much differently that the way I picture them now, simply because of the illustrations.
Another example that is a bit more extreme is the Invention of Hugo Cabret. The entire book is mostly illustrations and maybe 30% of it is actual reading. But somehow, it really works in the book's favor because of how it was written.
Then there's something that I say would be an interesting twist, especially with a digital platform, is something that the game Device 6 did, where the novel became the map of where you wanted to go or where the character wanted to go with pictures strewn about.
Once the Tapastic Novel section comes about, I'm thinking of participating.
