Duke Nukem has some atmospheric music that seems to be overlooked. For instance, Layers of Dust would fit in a Doom level nicely. So would Plasma (duh), Lemon Chilllll, In Tents...
I think it's a bit sad that, when people think about DN3D's music, all they can think of is "Grabbag" (which I personally feel is a way overhyped and dull tune.)