If you do a lot of spy work or work in a highly secretive environment, then you need to keep a lot of info under wraps so that no one gets the wind of it. Aiding you on you mission to data secured is this new self-destructive DVD by a German company. Called the Einmal (German for once), the disk is coated with a special chemical and can only be watched for 48 hours. There doesn't seem to be a DRM method on these discs. However be sure to leave no backups on other normal disks.

The Einmal costs about €3.99 ($6.44) a disc.

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