Audacious

What does the plugin do?
What license is it under?
Are you the author?

I don't think we need to support libvgmstream because basically all of the formats supported by vgmstream are also supported by ffmpeg. Do you have a file set that isn't well supported by ffmpeg?

The plugin is an input plugin which adds support for a number of obscure formats used by recent Nintendo consoles, GCN - WiiU.
People have ripped the tracks out of Super Smash Bros Brawl in particular, which was known for its large tracklist and soon began substituting other tracks in, which meant turning into a compatible format. Examples can be found at http://smashcustommusic.com/game/36
Notes on the license are currently at https://github.com/losnoco/vgmstream/blob/master/COPYING
I am not the author, I do not know how to contact users on github
Obscure formats which I do not believe are covered by ffmpeg are BRSTM, BCSTM, BFSTM

Looking into vgmstream was actually the reason I recently (re-)discovered Audacious (before then I was making do with Winamp over Wine). I don't think ffmpeg readily handles the myriad of streaming formats used in console games, especially recent ones from Nintendo as Jarrod mentioned. While I found Audacious could handle ADPCM-based formats just fine 'out of the box', there are still some formats that weren't recognised until I added vgmstream.

@Jarrod, I was able to add vgmstream by following the build instructions provided on their site. I suppose it would be nice if vgmstream was included in Audacious as plug-ins for 2SF, PSF, etc, already are but fortunately the compile and install process wasn't too hard. Since Audacious is Linux-based, I'm guessing the technical proficiency of the average user would be somewhat higher than the average Windows user.