If you've used an Oystercard on the London tube, you've used what is called Near Field Communications (NFC). You get the card near the reader rather than having to make physical contact. Such contactless tickets or passes are common in Europe; key fobs, for example, open office doors across the UK. In Hong Kong you can use the same Octopus card to pay for bus, train and ferry journeys or to buy a cup of coffee or an ice cream when you get off the bus. And anything that's small enough to build into something the size of a credit card can be built into a device you already own, a device you already carry with you every day - your phone.
In some surveys people claim they'd be more worried about leaving their phone at home than leaving their wallet behind; with NFC, your phone can be your wallet. It can be your train ticket, your library card, your supermarket loyalty card, your gym membership, your cinema ticket, even your credit card. According to Nokia's Gerhard Romen, "touch becomes the new click".
And if you want to know why France will get it before we do, read my piece at TechWeb