FeedDemon, hands down. It has the most efficient interface I've seen in a feedreader, and has been continuously improved since I started using it several years ago. The integration with newsgator online is killer, because it syncs your read flags so you to use FeedDemon client on one or multiple machines and also read through the web interface if you're not at your machine.
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Chris Hynes SlickUpload ASP.NET Upload component