Sometimes when I re-image my computers with a new OS I like to start my music library over again, just to see what I'd miss. Instead of pouring all of my files into one folder, I take only, say, the music I've gotten in the last two months and just listen to those songs.
When you start with a small base and build up (or set up any other sort of arbitrary limits) then you find out what music you listen to a lot, and what music you do not.
Naturally this is hard to maintain over many computers. My music library is somewhere between 500 MB and 12 GB depending on what computer I'm on. And while I'm pleased with my iPod on the hardware level, it is difficult to keep that poor player managed on the software side, especially when I'm using iTunes (which likes to delete an iPod's library if it smells something foul). Linux is quite good at syncing with the iPod, though there are flaws sometimes.
There's also the notion of what kind of music software to use. I'm a large fan of simple, single playlist windows like Audacious, but the visual database look of Rhythmbox helps me find songs in a large set.
All of this is a bit hard to manage at times (though for music, I make an exception in my minimalist philosophy!) so I'm trying to standardize some sort of middle ground that I can agree on house-wide. It will probably involve syncing my computers with my portable hard drive in some fashion.
This is a Linux website after all, even if the trouble of music management is an OS agnostic one. Is there a Linux solution? Maybe a small bash script that copies over any new files automatically? Perhaps I can even turn one of my less used desktops into a Vortexbox installation.