I typically have three CDs I pop in at work (I don't listen here as often as I'd like because it lets people sneak up in my cubie).

• Depressing Mix - a bunch of dark and depressing songs in minor keys, like Marilyn Manson's cover of "Suicide is Painless," several tunes from Nick Cave and the Bad Seeds Murder Ballads, some Pink Floyd, etc.
• Irish Folk Mix - The Irish Descendants, The Irish Rovers, The Flying Fish Sailors, and others.
• Metallica - my old standby, 9.5 hours of Metallica mp3s I ripped from my cd collection at home and burned onto one disk. Whenever I need something loud and angry in the background, I go with this.

At home, I'm much more diverse, listening to everything from Bob Marley to Beethoven to Megadeth to Rush to Thomas Dolby... With everything ripped to my hard drive, I can follow whatever whim suits me at the moment. I tend to keep it quieter, since I do most of my coding while the rest of the family sleeps.

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He seemed like such a nice guy to his neighbors / Kept to himself and never bothered them with favors
- Jefferson Airplane, "Assassin"