visualizing agile projects

I found this article today via the crystalclear list I follow: http://www.infoq.com/articles/agile-kanban-boards

Several of the described information radiators will already be familiar if you've been following agile. The most novel - one I have no choice but to love - is the "Smiley Calendar" ;) Seriously, getting feedback on team morale this way seems like a great idea; it gives team members who don't like to complain a way to quietly raise a flag when morale starts to suffer. Have any of you used one?