Inspired by this article : http : / / w ww . online-tech-tips . com/computer-tips/hide-file-in-picture/ [remove spaces] I decided to attempt the same thing on a mac. I managed to successfully hide the file: cat picture.jpg hidden.rtf.zip > picture2.jpg results in a picture (picture2.jpg) that is the size of the sum of picture.jpg and hidden.rtf.zip. I presume this means that I am successfully putting hidden into the picture. I can open picture2.jpg, but I can't figure out a way to access the hidden zip. Any ideas? Thanks very much in advance! Have a great day.