I didn't see this listed. http://www.gcstar.org/
Here's what is can manage:
* Video games
* Board games
* Comic books
* TV shows episodes
* User defined collections
I know some people don't like GTK apps, but everything is included, no screwing around with external addons.
Here's a link discussing the portable nature of it, the author's response is at the end. http://forums.gcstar.org/viewtopic.php?id=738
The executable just unpacks the files to a folder of your choice. Also Uniextract can unpack it.
So far I'm using it and like it, hope someone else finds it useful.