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Hiding files in other files (such as images)

See also Steganography
  http://en.wikipedia.org/wiki/Steganography

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Image message hiding

  http://mozaiq.org/encrypt/

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RAR files in PNG images

RAR files can be added to end of a PNG file, the still decode!

Hide
   rar a archive.rar file
   cat archive.rar >> picture.png

Extract
   unrar x picture.png

or extract specific file
   unrar p -inul picture.png file

Best to make sure picture is reasonably large!

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