Although we leave traces of our personal lives with our credit cards and Web browsers today, tomorrow's mobile devices will broadcast clouds of personal data to invisible monitors all around us.

We know more about our credit cards than we know about our bodies.

Credit cards are like snakes: Handle 'em long enough, and one will bite you.

But they couldn't, because the addresses associated with their credit cards were Quackistan or something; they were in such a high-risk country that the credit card companies wouldn't approve the purchase.

I don't have a wallet. I carry my driver's license and a couple of credit cards in my phone. That, and a money clip.

Credit cards are certainly not a ubiquitous payment system, but mobile phones are. We are monetizing it, both through the Internet and your mobile phone.