Contrary to popular belief, merely deleting files from your PC
won’t insure that no one will be able to read them. It’s not at all
difficult for someone to re-create your files, even after you’ve
deleted them from the Recycle Bin. Digital Document Shredder solves
the problem by using sophisticated algorithms for deleting,
overwriting, and shredding files. It offers multiple levels of
shredding security, including, it claims, standards used by the
Department of Defense and National Security Agency.
There are a lot of nifty extras in this program, such as shredding automatically saved previous versions of files in Vista, and shredding traces of your Internet history. You can either use Digital Document Shredder itself to delete files, or else right-click them, and delete them from inside Windows Explorer. You can even view all files on your hard disk that have been deleted, but not yet shredded, and then shred them.
–Preston Gralla