Digital Document Shredder

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