We game in in the same room as my PC, or online over mIRC. Game's about 45 sessions deep so far, and we've got a TON of music. I've about 18 or 19 battle themes, different themes for each city, theme music for my NPCs, themes for the villains, some scenes that have happened have had their own themes, and then I also have mood themes, if party conversation starts heading a certain way. The count so far is 110 themes, including about 20 I have saved for later events.
Sample artists and soundtracks include: Baz Luhrman's Romeo & Juliet, Cowboy Bebop, Nine Inch Nails, Linkin Park, the Gladiator soundtrack, Chrono Trigger, .hack//sign, Rent, stuff from Metal Gear Solid 2, a Nike commercial, the Lion King, Michael W. Smith, the Matrix, Riverdance, and World Wrestling Entertainment.
So I use music pretty intensely.