Battery life indicator t-shirts! A convenient way of indicating your current degree of hunger/fatigue/optimism/whatever.
You're in a good mood – spread it around! Or you're not – let people know to get the hell out of your way.
Why wear a gold t-shirt with a black fleur-del-is? Well, so you can see at a glance who's on your side – and more importantly, who isn't.
Do you tell people what to do and who to do it to? Or are you the person who typically winds up getting told and/or done?
So you're awesome and you're looking for a tasteful way to let people know about it. Low-rating designs also available for those with self-esteem issues.
Shōgi is Japanese Chess. Well, kind of. The pieces and the rules are different, but the social dynamic is basically the same.