People talk about the digitisation of the world - or at least, of the world of knowledge - and the coming ubiquity of digital storage, and every once in a while you glimpse the reality of it.

One of the exhibitors at the recent Infosec show in London, a company called SmartLine, asked visitors to its stand if they were carrying any portable storage devices - memory cards, USB sticks, MP3 players and so on - and if so, how many.

I wasn't hugely surprised to read that 90 percent said yes, and that the average came out as 1.8 per person. After all, I had three myself, not including the laptop hard disk, and some people claimed to have six or more.

For SmartLine, the big thing was that 80 percent of the people it asked said they believed their organisation had lost confidential data via such devices - it said this hinted at huge complacency. It sells USB port-locking software, so while the point is valid, "Mandy Rice-Davies Applies"...

What I found interesting was to multiply the individual figure by the total number of attendees, which was around 11,000. It makes some 20,000 storage devices, and if we assume half a gigabyte per device (based on my own count) that's 10 Terabytes in total.

Of course, there's no word on how much of that was empty, duplicated or whatever, but still - 10 Terabytes of storage, wandering around in peoples' pockets. We do indeed live in interesting times.