I'm the opposite of someone with a poker face. Whatever I'm feeling, for better or worse, is revealed in my facial expression.
So I'm not sure how much I'd really need The Daily Mood Flip Book that tells my co-workers that I'm "spent," or "grumpy" or "exuberant." (Or whatever.)
How weird would it be to go to someone's desk to borrow their stapler or ask for a piece of gum, only to see a sign that implies, passive-aggressively, that you should go away or stay? But that's just me.