If experiments in San Francisco prove successful, you could soon see your name displayed on a poster site near you.

And, once you have recovered from the shock, you will probably not be surprised to discover that you have your mobile phone to thank.

Because your network operator, who of course knows the precise whereabouts of your handset every second you have it switched on, will have informed the poster contractor that you were about to pass the site in question.

Then, because you were amongst those the advertiser who had booked that site was trying to reach, digital technology instantaneously married your name with their message.

For example say you were Joe Soap, commuting in to London each day by car from Oxford. All too often you are likely to find yourself sitting in a traffic jam on Western Avenue, going nowhere quickly.

First Great Western, the train operating company on the Oxford line, will have done a deal with both a poster contractor owning one or more of the poster sites on Western Avenue and your network operator.

They would have specified that they want to reach people who live within a three-mile radius of Oxford station and who drive in to central London every day. More specifically, they stated they only wished to reach those people when they were stationary in their cars within fifty or fewer yards of those poster sites.

From the data they capture and the fact the location of your phone hasn’t changed in the last 5 seconds, your network operator knows you satisfy each of those criteria.

So there, on the poster site before you, you suddenly see the message appear: “Joe Soap, why are you wasting so much of your life driving into town? Today you would already be at your destination. Had you let the train take the strain.”

Similarly, when you later walk in to a shopping centre, Mastercard might choose to inform you that you could win a free holiday if you charge more than £50 to your card today.

Needless to say, advertisers will be prepared to pay a healthy premium to target their messages with such precision.

So, for both poster contractor and network operator, this is an attractive proposition. But whether you will be happy to see your name plastered across a billboard is another matter.

Inevitably there will be some way in which you can opt out. But you can be sure that the onus will be on you. Your network operator is certain to rely on implied consent, a subject we will return to elsewhere on this blog.

Your network operator will also try to reassure you by promising no personal information will be passed on to any advertiser. But that is hardly the point. Between them the poster contractor and network operator will have already used their technology to plaster your name in front of your face. And the same message you saw will have also been seen by anybody else who happened to be passing at the same time.

Try explaining that away should you be other than where you were meant to be.

Clearly there is a very real danger that those targeted in such a public and intrusive way will object strongly. In fact the negative response could be so great that the reputations of the advertisers involved will be badly damaged.

We shall see how the citizens of San Francisco react. You can but hope they will be less than impressed.