FeedDemon started out as a commercial RSS reader, but it's now the desktop version of NewsGator's online RSS reader.
It syncs with a central account, but presents your feeds within a fast, well-designed application that uses the web version as a backup. That's good, because the online NewsGator is a bit stodgy for our liking.
Unlike many desktop clients, you can clip things of interest and sync them across PCs, while the Watch tool is perfect for pulling in millions of different feeds but only presenting the relevant bits via saved searches.
FeedDemon is good for promoting the feeds that you use the most and handling podcasts. It also features a brilliant Newspaper view that displays a subset of a particular feed or category, and is accompanied on the iPhone by NetNewsWire – a free program from the App Store that does a fantastic job of letting you take unfinished reading material on the move.
All this makes for a complicated but powerful suite of tools for staying connected. The addition of Google Reader support would make FeedDemon a tough aggregator to beat.