How Many Things Have EVER Been Invented that People Carry ALL the Time?

An IDC survey has gotten some gee-whiz attention because it found that 38% of respondents would choose their cell phones over their wallets if they had to leave one behind. But there's something more fascinating about the question itself.

In all of modern, Western history, only a few items have EVER been invented that most people choose to (or must) carry on their bodies most if not all of the time.

The list looks something like this, in rough historical order:

Money

Keys

The watch

Identification (driver's license, etc.)

Credit card

Cell phone

It's kind of amazing to know that we're witnessing a remarkable event in human history -- the rise of the first electronic, connected gadget to become a personal item as important as money or the watch.

But here's the more amazing thing: the cell phone could -- and should -- usurp and engulf all the previous personal items. Stories have been noting for a while that watch sales are down because people just rely on their cell phones for the time. Around the world, consumers are beginning to store credit card information in their cell phones and pay for items by beaming a code to a cashier.

Logic says it's only a matter of time before a cell phone can be your keys, too. Think about the wireless access and ignition in the Toyota Prius. That code could be stored in a cell phone. Your home could similarly have wireless locks that open when you touch a code on your cell key pad.

In time, ALL you'll need to carry is your cell phone. It will be keys, ID, credit card, money and a lot of other stuff. (Can Nokia squeeze in a make-up kit?) This latest survey shows only the tip of what's coming.

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