By David Calder
BBC Radio Scotland's The Investigation
Not so long ago, the Information Commissioner warned that we were "sleep-walking our way into a surveillance society".
There are estimated to be up to 10 million CCTV cameras in the UK
At the time, a lot of people assumed he was talking about CCTV cameras.
But it's now clear he was more concerned about the amount of data held on each and every one of us which, if all brought together, would give the government an incredibly detailed view of our lives.
It was brought home all too clearly when Alistair Darling stood up in the House of Commons last month and admitted the loss of those CDs by HM Revenue and Customs.
You may have thought we had some protection from the Data Protection Act.
But Dr David Murakami Wood, a surveillance specialist from Newcastle University, believes it was out of date even before it came into force.
"It's based on a 1970s conception of computing," he explained.
"It came long before the networking of computers. You could now argue that how we exist in databases is as important as how we exist in the real world."
He edited a report on the surveillance society for the Information Commissioner. It makes quite disturbing reading, especially when you think about the plans for a national ID card.
"The National Identity Register will hold up to 50 pieces of information," he said.
"Everything from your national insurance number to your health record to the number of penalty points on your driving licence will be stored there, even information about when you buy a mobile phone."
That mobile phone is also storing a surprising amount of information about you.
From the start of October, the mobile phone companies will have to retain data about who you were calling, when you made the call and where you were when you made it.
And that information won't just be available to the police.
According to Geraint Bevan of No2ID, 650 other organisations will be able to see it as well, from the Gaming Commission to local authorities.
"This data will be logged for a year," he said, "and every minor official could be able to have access to your phone records. There's no privacy anymore."
Then there's data from CCTV systems.
There have been various estimates of how many of these there are in the UK.
But Camera Watch, the industry body set up to ensure that systems are compliant with data protection, believes it's largely educated guesswork.
The numbers range from about four million to 10 million - no-one actually knows.
On top of all this, there's the data collected on you by the private sector.
Dr Murakami Wood said people are putting too much data on sites
If you use a loyalty card in a shop, that information is stored to build up a picture of your preferences.
Even more is gathered when you shop online. Banks and insurance companies also gather data about you and not everyone is convinced that it's all strictly necessary.
The human rights lawyer, John Scott, is worried by the way it's monitoring our lives but acknowledges that "you can't turn back the tide of technology".
He said: "We should stop and think about where we'll be in five or 10 years time. We should be trying to stop the unthinking proliferation of surveillance systems before it's too late."
Dr Murakami Wood, however, thinks we've brought a lot of this on our own heads by "putting so much of our own personal data up on Facebook or MySpace".
He added: "It's made officials think we don't value privacy any more."
He believes it's time for the country to have a serious national debate about our surveillance society before it goes any further.