The Ad Agency With Headquarters In A Phone Booth

As well as creating business cards that can be folded into the shape of a telephone booth, New York-based advertising agency Clark&Kent have taken the joke one step further, becoming "the ad agency with headquarters in a phone booth in New York."
The agency are clearly good at spreading their name, as the business cards have appeared on design blogs across the world, but for now they're not giving away any additional information. All it says on their website is "All we can tell you is that we are the smallest advertising agency in the world. Contact us by mail, bat-signal, and even by phone."