I have to admit that I first found that exercise in a different book called Becoming a Writer by Dorothea Brande. However, my mum had a copy of The Artist's Way - along with the hundreds of other cool books that were lying around the house when I was growing up - so of course I dipped into it and I've heard it mentioned in various circles since then. Seems that it's played a similar role for a lot of people. So glad to hear it was such a help for you. Depression is a horrible beast when it rears its ugly head.