mirrorlinks project is a small script that automatically mirrors the contents of a directory into another directory using symbolic links, so you don't waste unnecessary disk space in copies.
This is better explained by example, of course:
You have directories Music, Movies and Shared.
You want to mirror both the contents of Music and the contents of Movies into Shared. For some specific reason, you don't want to place links to Movies and Music into Shared,
With mirrorlinks, that's easy to do:
mirrorlinks Music Shared
mirrorlinks Music Movies
Now Shared has the contents of both the Music and Movies directories. To be more accurate, Shared has the directory structure of both Music and Movies merged into one single directory, with symbolic links pointing to the actual files. So if you had files into Music/ATB, Shared would contain a folder named ATB, and this folder would contain links to the files in Music/ATB.