NetNewsWire, another awesome RSS reader on the Mac is $39.95.
However that said, PulpFiction is just damn amazing and I love using it. It's simple yet powerful like Mail, filtering RSS posts by topic or general thread area is wonderful, or even setting labels so they stand out if they contain certain attributes (eg. Important stuff from the MacRumors feed, or contains profanity).
It's a beautiful product and worth at least a look.