Opinion: Perspective - Philip K Dick: sci-fi's bestselling author ... and ad visionary

I suspect many of us have sat through a presentation that contains scenes from Minority Report with Tom Cruise playing with big computer screens with his fingertips or walking through a mall with an "intelligent" poster importuning him with: "John Anderton. You could use a Guinness right about now."

I always wondered how intelligent that poster was. Did it take a shot in the dark and assume almost everyone could use a Guinness right now or did it have a deeper insight into the trials and tribulations of John Anderton's day? The answer is the latter and now I see how.

The premise of the story (by Philip K Dick) is that the "Precrime" division of the police employs three "precogs", mutated humans who can see fuzzily into the future. If two out of the three precogs see someone about to commit a violent crime, the police rush off and arrest them before they do it.

This is an interesting idea: arresting someone for something they have not yet done. And it gets more interesting when you think that this is what we do as an industry - arrest someone's attention just before we think they are about to do something. But what if we could do better than just "think" they were about to act and could do it without using odd-looking mutants in fish tanks?

Very soon, we will be able to. At the lowest level, we already do this. If you know every time I search for a hotel in a foreign country (Google), I then book a flight three days later (Expedia), then it is easy to react to my hotel search and send me an offer for a flight.

This is about the behavioural insights gleaned from mining the connections between inter-related databases and the algorithms that link them to subsequent actions, and it is getting richer by the minute.

Search, financial, travel, mobile phone calls, health, legal, movement and location will all be in the mix. Forget "people who bought that also bought this". Intelligence services are already mining data to determine "people who just did what you did went on to do something bad later".

We will do it in marketing too. My Google profile says I searched "triathlon" and "chafing". My credit card says I fly to Barcelona tomorrow. My doctor records the fact I have a delicate problem. The ATM says I have £100 in my pocket. And my phone says I am on Oxford Street this minute.

Bang. The Adidas machine adds this together and sends me a "25 per cent off coupon" for their extra sensitive, extra small swimming trunks and directions to the store. Crash. An impulse purchase is made. Wallop. My testicles are spared.

Those of us who do not currently have a handle on data techniques and real-time, proximity marketing had better sort things out soon because the machine already knows who you are.