The other day I took a taxi from Pittsburgh International Airport to a meeting downtown. I had an important meeting, and my assistant, Rachel, wanted to be sure I got there on time, so she pre-arranged ride through “Richie’s Cab Service.” As I walked through the terminal, I dialed and Richie himself answered. He’d be there in ten seconds. And he was. I’m not kidding. Within 20 minutes, I arrived at the Omni Penn Hotel. The only rub, I thought, would be payment. A sign was taped to the credit card machine – out of service. “Do you take credit cards?,” I asked. “Oh, sure!” he responded as he whipped out his mobile phone equipped with the new Square device. He deftly took the card, swiped it and handed it back. “Email receipt?” he asked. “Absolutely!” I responded.