Data Destroyer 

A program for secure file deletion and disk wipe which destroys (by overwriting) data in multiple files and multiple folders on floppy, ZIP or hard disk so that the data cannot be recovered. Single-file or batch-mode operation.
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Mutilate File Wiper 

Mutilate File Wiper is an easy to use file eraser that shreds sensitive files so they cannot be recovered or undeleted. For additional security, Mutilate's disk free space wiper will destroy previously deleted files on your hard drive.
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PowerKey 

PowerKey is an advanced encryption toolkit with many unique features which you won't come across in other products of such a kind available online. It allows you to perform block encryption of files and folders, wipe and other.
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