This plugin allows you to write XMMS plugins as Unix programs. You write a program that understands the very simple commands on its command line and outputs raw sound on its standard output and you're done with it. What's good (and in fact the purpose of this plugin) is that you can write input plugins for XMMS in C shell or Bash! Of course, you won't be able to do much number crunching in a shell script, but you can use it to run other programs to do the actual playing.