I love NetNewsWire1 — and have for years — because its interface isn't overdone, and because of how fast it lets me get through whatever's new. I have it set up a little bit different from the default to make things even more focused and minimal.
Hidden Feeds List
I primarily get through my news by repeatedly hitting ⌘ + / (next unread)2, so I have no reason to look at my list of feeds unless I'm removing, reorganizing or adding feeds.
Tabs and Open Links in NetNewsWire
Setting tabs to appear at the top of the window keeps it from resizing to show them on the right, and cuts down on visual clutter while reading. I have the app set to open links in NetNewsWire by default, so when I'm going through my articles list hit, I can hit return (open article) if I see an article I want to read in more detail, and click links that sound interesting, and they'll come up as tabs. I keep them open and use as a queue of things I want to read in more detail (or, ⌘-P to send to Instapaper if I realize I don't have time right now).
Ballard 21st Century Theme
A theme for NetNewsWire by Alex Knight, based on a theme by Pat Dryburgh, which was based on the original that Brent made. It's really nice. They share no actual CSS, but the theme of this blog is clearly heavily influenced by it. I honestly can't remember if that was on purpose or just came from staring at this theme every day. The point is I like it a lot3.