I came across this post a few months ago and the idea stuck. I am working on a project at the moment that has just gone live and is about to progress to the next stage where a significant amount of functionality is due to be added.
One of the key screens has been implemented but requires significant changes. I was on a conference call to discuss this where the business representative obviously had a reasonably clear idea of what was required but no-one else did. As past screens have been a bit of a battle I suggested he draw out what he had in mind, using pen and paper. Initially he was keen on this however in the end he reverted to mocking it up in Excel (it's basically a grid anyway). At least he didn't resort to Visio or the development environment.