Don't weep now, but Cambridge University's famous Trojan Room coffee pot webcam is going offline. The university's computer laboratory is moving to a new building to the west of Cambridge later this year.

The webcam will no longer be needed to tell staff, and the world, whether there's a cuppa still left in the pot. The history of the camera shows how a solution to a simple problem can forecast technological innovation.

Quentin Stafford-Fraser set up the original camera in 1991 to an internal network to ease a source of tension amongst staff at Cambridge's computer lab, known as the Trojan Room. Some members of the lab's coffee club were fed up with walking halfway around the building to the coffee room only to find the pot empty.

Stafford-Fraser and a colleague wrote a program which allowed a camera to capture images of the pot every few seconds at various resolutions and allowed staff to see an icon-sized image of the pot in the corner of their computer screens.

"The image was only updated about three times a minute, but that was fine because the pot filled rather slowly, and it was only greyscale, which was also fine, because so was the coffee,'' Stafford-Fraser explains at the webcam's site. ''This system only took us a day or so to construct but was rather more useful than anything else I wrote while working on networks.'' Soon afterwards two other staff put the cam on the Internet, with a new frame every second, becoming the pioneers of what has become a mass online fad. The media got interested and millions of viewers flooded the site. There wasn't much on the Web in those early days, so the picture of the coffee pot became a kind of cult.

If you're nostalgic check out the coffee in Cambridge at http://www.cl.cam.ac.uk/coffee/coffee.html.

I've always been puzzled when doing searches on my computer for a particular file that I've stored somewhere, to discover displayed among the results cached web site files in an folder labeled IE5, which itself is imbedded in the Temporary Internet Files folder.

When I open the Temporary Internet Files folder (in the Windows folder in System) there were no files displayed. I regularly clean my Internet cache (which stores files and web pages you've visited while surfing) and temporary file folder using the disk cleanup utility that comes with Windows, so it bothered me that these errant files took up space on my hard drive.

Early webcam goes off the boil As my Internet Explorer browser began crashing more and more frequently I decided to find out if these mystery files were the source of the problem. The conclusion -- maybe or maybe not. But in the process I found about 22,000 hidden files taking up 78 megabytes of space in the IE5 folder, the leftovers of months of intense surfing.

Here's a little strategy that could help you win back some space on your hard drive and ensure that your Internet cache is unclogged of useless files. It seems that every time the browser crashes cached files get lost in limbo on the computer. They really remain in the Internet Explorer cache folder but are not displayed.

While some tech professionals on the web have devised instructions elaborating how to delete the files in MS-DOS, I found the process complicated and potentially catastrophic for a novice like myself.

I decided to take the tedious method. Here's what I did instead. Warning -- don't do this unless you're relatively knowledgeable about messing around in the Windows system folder and have made a back-up of important files.

To see if your temporary Internet files are getting cleaned up use the Find -- Files or Folders utility and type the path to the Temporary Internet Files folder like this (unless you've moved this folder): C:/Windows/Temporary Internet Files. Hit Find Now and presto any files in the folder are displayed.

I found it easier to then manually select a couple of thousand files at a time and then delete. Do not delete any folders, the "index.dat file'', or the ''desktop.ini'' files. Everything else is junk. The delete process has a safety feature that automatically queries whether you really want to delete the files. Just select `No' when asked. I had a lot of selecting and deleting to do, but it was worth it I think. This is just one of the many quirks of Windows and Internet Explorer one has to live with.

Tech Tattle deals with topics relating to technology. You can contact Ahmed at editor yoffshoreon.com or (33) 467901474.