Not to bring up Mr. Reznor again but have you considered any of the tracks from the Ghosts I, II, III, IV album?
Ghosts - Home
A lot of people aren't aware of this album because it is ENTIRELY instrumental.
I love to listen to this album in the car because, it takes you back and forth from somber, melancholy, enthusiastic, to angry.
You can listen for free if you click the listen tab in the upper right side of the page.
just another random suggestion.