Personal Story
When Apple launched the iBookstore, I was told that it was impossible for us at my company to develop the functionality to be on there at launch. I challenged this assumption and found ways to create an uploader and front end and on the side of our systems, to "mechanical Turk" the project in order to be on time for Apple's big launch.
Self Assessment
9 - I often look at a problem and posit the opposite not just to play "devil's advocate" but to challenge assumptions, searching for ways of removing blockers, improving processes, and creating products.