Nothing can match that feeling of relief you get after recovering data from a disk you thought was destroyed. In its “Museum of Bizarre Disk-Asters,” DriveSavers disk recovery company offers client testimonies dripping with relief and gratitude, plus photos and case studies about recovering data from laptops crushed by buses and desktops destroyed in fires. But what if you wanted that data destroyed and instead it surfaced in strangers’ hands, recovered from a hard drive you thought was sanitized?

Over 40 percent of the hard drives sold on eBay still contain sensitive data that users thought had been purged, according to computer forensics company Kessler International. Recently, the company as an experiment randomly bought hard drives on eBay and set its forensics engineers loose on them, surprising even them with the amount of data still recoverable. To purge data from your hard disk drives, you have several choices (besides setting fire to them, or driving over them with a bus, which, as mentioned above, doesn’t necessarily work): Overwrite the data or physically destroy the disk. Or, if you want a cleaner solution than the power saw used in the preceding link, you can degauss it with a magnetic device.

Degaussing, as you know, is the process of applying a reverse magnetizing force to a magnetic storage device. This renders the data stored on it unreadable, unintelligible, and unrecoverable “by any technology known to exist,” as the National Security Agency says in its 2007 “Degausser Evaluated Products List.”

Fujitsu’s Mag EraSURE degausser is one such device. It deletes data on any type of magnetically recorded storage media—zip disks, floppy disks, backup tapes, hard drives—by exposing it to a rare earth magnet, the strongest manufactured magnet available. Fujitsu reports that a DriveSavers data recovery team examined three enterprise-quality hard disk drives that had been processed through the Mag EraSURE device. DriveSaver’s engineers disassembled the internal components, examined the media and head stack with a microscope, and concluded that there was no data that could be recovered from the disks.

Degaussing with the device is simple: You insert a hard drive in the device, which is about the size of a breadmaker, though it can weigh from 60 to 240 pounds. Depending on the size of the hard drive, you can degauss more than one hard drive at a time. Mag EraSURE P3 version 2 degausses a drive in 15 seconds. Another version of Mag EraSURE degausses in 10 to 20 seconds and runs via a hand crank, for when power is cut and data must be deleted immediately (think “the embassy is about to be overrun by rebels with data recovery skills and we must get rid of this sensitive information”). Government agencies are a huge customer, as are enterprises that must dispose of sensitive data.

Based on experience gained (ironically) from manufacturing hard drives, and anticipating future changes in storage technology, Fujitsu says its devices should still be able to destroy data on future hard disk technology in use five and 10 years down the road. The P3 version 2, which can also degausse VHS tapes, runs about $53,000, a cost that’s admittedly less significant than the cost of a data breach, especially for companies that retire hundreds or thousands of computers a year.