Proton Pack with Speakers?

Just wondering of anyone has done a proton pack with a hidden speaker? I was thinking it would be cool to have a working speaker so I could dock my iPod in my pack and have it play Ghostbusters by Ray Parker Jr, as well as some of the other featured music from the movies. I suppose sound effects too. I think a speaker would be pretty easy to hide inside the pack. Any thoughts? Has it been done to death?

This is a tutorial on how to add all of the sounds you want, including adding speakers, amplifier and sound module with all the sound effects from the movies and music

http://www.gbfans.com/community/viewtopic.php?f=42&t=14730