Attach File Inside PDF
Source: https://tex.stackexchange.com/questions/18271/include-binary-data
This allows you to include (embed) a file in the output PDF like an attachment. It is easy enough to get the base functionality. You just add a use statement
\usepackage{attachfile}
then just add the attach command (in the example the file is called a.tar.xz)
\attachfile{a.tar.xz}
To get the file back out of the PDF I have found mixed support in readers but Firefox allows you to double click on the icon that is generated and opens a download dialog.