Sometimes silence cuts it for me, but otherwise, yeah...mostly without lyrics though, as I tend to find those distracting...usually I'm going for an emotion/vibe. For inspiration though, I find Bob Dylan, Tom Waits and Nick Cave good to listen to, to name a few. Anyway:
Epic
Led Zep epicness
IT DOESN'T GET MORE EPIC THAN THIS
Bit more epicness there
Uhhh...more epicness?
Ok, there's just too much epicness around here!
Fine. You want some fries with that epicness?
Ok..ok..no more epicness...after this song :p
Sad
Saaad
Always makes me sad...
More sadness with nostalgia and wistfulness all mixed up in there
Surprise! More epicness...
Dark
Even darker (yep, that scene)
Bittersweet..happy but kind of sad...but ultimately happy. Idk :P
If I just need to concentrate/'get in the zone' though, classical (Beethoven, Chopin, Mozart, Mahler and Tchaikovsky..) and jazz (Herbie Hancock, Clifford Brown, Chet Baker, Eric Dolphy, Miles Davis..) music is the thing. The Shadows and The Cinematic Orchestra are also great for that, though I tend use the latter for mood/emotion more than concentration.
And it depends on what I'm writing too...if I'm writing an apocalyptic story, I tend to alternate between this and that. Right now, I'm writing an epic Tintin fanfic, so...yeah...:)
Not sure if you even wanted all that, but...you've got it now lol.