AmphetaDesk is a free, cross platform, open-sourced, syndicated news aggregator - it obediently sits on your desktop, downloads the latest news that interests you, and displays them in a quick and easy to use (and customizable!) webpage.
BottomFeeder is a news aggregator client (RSS and Atom) written in VisualWorks Smalltalk. BottomFeeder runs on Linux x86, (also FreeBSD), PowerPC Linux, Sparc Linux, Windows (98/ME/NT/2000/XP/CE 4), Mac OS8/9, Mac OS X (PPC, intel), AIX, SGI Irix, HP-UX,