There's a lot to be said for surfing the web. It's really quite amazing what you can find when searching for something totally different that may have no (apparent) link to the amazing stuff you get to discover.

This week by sheer accident, I came across an item on the BBC's web site in their magazine section entitled "The search for photos of China's past" (www.bbc.co.uk/news/magazine-18784990). If you have a few spare minutes I would strongly recommend you take a look. "Historical photos are rare in China," it says, adding that many were destroyed in the Cultural Revolution. "But now the country's past is being reclaimed."

It goes on to describe what they call "old photograph fever" currently sweeping China, and the lengths some people are going to in order to dig up historical photographs – many of them kept safely hidden away in foreign countries.

I guess there is an inbuilt fascination in seeing how places and people have changed over the years. I know that one of the first things I do when visiting somewhere new is to research old photographs and get a feel for the place and how it used to be. Of course, so much has changed in China over the past few decades that there is an endless fascination with seeing how life used to be here.

But China is not alone in the dearth of photographs available. I remember when I was researching a book about Saudi Arabia's capital Riyadh, the amount of pictures available from historical archives was meager to say the least. Given that only 50 years ago that country, along with most of the Gulf region, was only just making its transition from tents and mud brick houses to the ultra-modern metropolis of today, the call for old photographs is as loud as anything heard over here in China.

The Saudis, of course, did not have a cultural revolution; but instead had – and still have to some extent – a very fundamentalist take on Islam which prohibited, among many things, making likenesses of any living creature – and that includes photography. Even today, street advertising posters regularly have faces of people pixilated out so as not to offend the hard line clerics.

One of the by-products of this is that photography was banned in most public places until July 2006. (I was actually arrested on one occasion for taking a photograph of a chandelier in Riyadh railway station. Not only was it a public place where women "might have been present" – but weren't - but being a railway meant it was also "strategic" and it was deemed I could be compromising state security!) Now, late in the day, the Saudis are desperately courting foreigners who might have taken surreptitious photos in years gone by, and are keeping copies in their historical repository at Al Turath.

I always make it a point of principle nowadays wherever I am never to go out without taking a camera with me. You never know what you will see from one day to the next. From the amount of pictures flooding the web, it appears that many other people do so as well. Of course, the fact that we all have cameras on our cell phones, and digital cameras are now both cheaper and better than ever before helps in all this. Yet it really wasn't that long ago (was it?) when I would think twice about buying a second roll of film for going on my annual holidays; for how could I possibly want to take more than, say 40 photographs on my fortnight's vacation? So much changes around us almost imperceptibly day to day that it is quite astonishing to compare "before and after" pictures of places you go to every day and see how much has changed over, say, a year.

And what will it be like in a century from now? Will we be recording the smell of a place, as well as the sounds and moving images? Quite possibly, if the techies have anything to do with it. Already one can get smell "printers" that contain 16 reservoirs of scents that it is claimed in combination can produce any smell known to man. They were first developed by scientists to be used when you were surfing the net and exploring an online supermarket, for instance. So, when you walk down the virtual bread aisle you get the smell of freshly baked bread wafting out of your smell-printer; and when you buy coffee you get the scent of freshly brewed coffee … you get the idea! So once we can also "record" those smells, as well as recreate them as we can do now, there is a whole new perspective on life that could be grabbing the attention of future historians.

Mind you, I'm not quite sure that I'd want to record all the smells there are around me. I think I must have been a dog in an earlier life as my sense of smell can be quite keen at times. But could you imagine going to a cinema in a century's time and actually smelling a scene being played out on an overcrowded subway train in the height of the Beijing summer? It doesn't bear thinking about!