6. Oyster Card
It might be a convenient way to pay for your Tube journeys, but think about what it says about your travelling habits. The Oyster Card can tell where started your journey, where you stopped off and what your final destination was and theoretically how long you spent in each place.
The police can already access the information and use it as evidence of wrong-doing. But what if the information fell into the wrong hands? Stalkers could have a field day.
7. GPS anything
The taxman's pursuing you for some money you owe. You claim you didn't earn any. So why are there photos of you enjoying holidays in the Algarve, the Bahamas and Brighton? How do they know? Blame your willingness to share your sojourns on Photo Bucket, etc and the fact that you left the GPS data, times and dates captured by your phone/camera intact.
Professional drivers and sales reps will already know that GPS data can be used to monitor your whereabouts in real time using readily available software and hardware. Just wait until insurance companies start insisting on having black boxes fitted to cars to identify culprits in accidents.
8. Itemised billing
Leave aside for the moment the prospect that any wrongdoing is likely to see your landline/mobile phone records displayed before the court. But how are you going to justify those calls to your lover/adult chatline/betting shop to your better half, when they can see exactly who you called, on what dates and at which times of day?
Ostensibly used to track the movement of objects from factory to shop, Radio Frequency Identity Tags (RFID) have already been used for more controversial purposes - from identifying potential razor blade thieves in supermarkets to actively tracking customers around shops to find out what they're interested in.
Tesco is already rolling out RFID-enabled loyalty cards to its customers, and data gathered from RFID tag enabled trolleys in one US supermarket is being used to track shoppers around the store and deliver in-aisle offers to shoppers as well as money-off vouchers at the checkout. Sounds great in theory, but do you want to have your every moment tracked for the sake of a few pence off a tin of beans?
10. Your web history
Anyone with a proclivity to visit certain kinds of website already knows how to clear their web history so it's not chanced upon by others, but Apple's Safari web browser attracted the contempt of users earlier this year when it was revealed that its Top Sites website feature kept snaps of the pages users visited even when they'd tried to hide their tracks using Private Browsing mode.
Apple fixed that with the latest version for Mac and PC. Users of other browsers might not be so lucky.