I'm a huge fan of Threadless and other ventures that express the hilarious, frivolous, and politically incorrect on T-Shirts. Self-expression for the upper torso and back.
My daughter Emmy and I are always trading ideas for T-Shirts to submit to Threadless. I have the artistic capacity of a stump, so all I end up with is ideas. Here's one of our silly ideas. You always see those silly "angel on one shoulder, devil on another shoulder" images, and I wanted to play with that on a T-Shirt. Humorous yet a serious question. You make the call.
I wish more T-Shirts engaged the viewer both front and back. You'd know you got someone's attention when they were so intrigued that they left their normal walking pattern and orbited around you for a brief moment to get the whole joke or story.
And on the topic of knowing that someone got your T-Shirt, I've been thinking a lot about what happens when our glasses move from passive to active data discovery. When we look at a person and not only see them (passive data) but also see their social graph status floating about their heads (active data). It would not kick ass if someone looked at your T-Shirt (wardrobe) and they not only got the passive data, but an active response stream? They see another part of the joke, perhaps? A wink of appreciation? And of course, I as the viewed would get an active response above their head letting me know that they looked at my shirt. Little problems emerge like determining the duration of the viewing (glance versus actual consumption), but our glasses will soon deliver much more than what the physical world offers in terms of data, and I want my T-Shirts in on the action!