unevenly distributed future: hong kong

kottke has a great writeup of his trip to hk. the octopus cards were most impressive:

...It's a pay-as-you go stored value card...you put $100 bucks on it and "recharge" the card when it's empty (or when it's even more than empty...as long as your balance is positive when you use it, you can go into a HK$35 deficit, which you pay when you recharge the card). You can use it on pratically any public transportation in the city: buses, trains, MTR, trams, ferries, etc. It works with vending machines, at 7-Eleven, McDonald's, Starbucks, and the supermarket. You don't need to take it out of your wallet or purse to use it, just hold it near the sensor. Your card is not tied to your identity...there's no PIN, you can pay cash, they don't need to know your credit card number, SS#, or anything like that. They even make watches and mobile phones that have Octopus built it, so your phone (or watch) becomes your wallet.