Want athmosphere for your sessions? There's some guy who has organised his music by category, and so on, and you can play it from his site.
Granted, the tracks are short, but you can loop most of them, and I'd generally use them for peak moments.
I'm planning to use it next time I run something (though at the moment I'm being a player in our WHoOG campaign and having lots of fun). But I thought you might want to know the site exists.
There are also textures you can use to...represent materials in games, or something. Not sure whether I'd use those ones, but whatever.
FWIW, I'm not affiliated with the creator of the site. Just saw it and liked what I'm hearing.