embed-ass is a Bash script that allows you to embed fonts into ass files and to extract them.

Command line arguments:
embed-ass <directory> <ass_file> attach files from directory
embed-ass <file> <ass_file> attach single file
embed-ass -x <ass_file> extract attachments

Examples:

embed-ass path/to/fonts subtitles.ass
embed-ass fonts/new-font.ttf subtitles.ass
embed-ass -x my/data/subtitles.ass

Installation:
Run ./configure and then make check install. You can specify a target directory with the --prefix option, i.e: ./configure --prefix=/usr

To convert the fonts, it uses UUEncode-simple from Youka which is already included here.

Known problems:
At the moment this script can't handle filenames without an extension or with a leading dot.