Here's the next essential item in a sysadmin's equipment - a hammer. Too many PCs are still dumped with confidential data intact according to Which? Computing, information that would be very tempting to identity thieves.

The consumer protection publication said that such was the ease with which data could be recovered, that smashing a hard drive with a hammer was the only solution for total peace of mind. The publication showed how easy it was to retrieve sensitive data from unwanted PCs by buying eight second-hand hard drives from eBay and trawling through them to see what confidential information could be uncovered.

Using easily obtainable free software, Which? Computing researchers recovered 22,000 'deleted' files, including images, music files and spreadsheets.

Which? Computing editor Sarah Kidner warned that the risk of falling victim is high as the average UK citizen was worth an estimated £85,000 to an identity fraudster. "PCs contain more valuable personal information than ever as people increasingly shop online and use social networking sites." She said that brute force was often the only answer; "It sounds extreme, but the only way to be 100 percent safe is to smash your hard drive into smithereens."

Which? Computing research closely mirrors that of University of Glamorgan's carried out last summer. The BT-funded research analysed 317 second-hand hard drives purchased second-hand and found that 23 percent of business machines contained enough information to identify the specific company that had owned them, and a shocking five percent still held sensitive business information.

If destruction sounds too extreme, there's always the option of encrypting all the hard disks. This could be an expensive option and not always reliable as researchers from Princeton University found last year when researchers showed that encryption such as BitLocker could be cracked.