Soundflower is a MacOS X (10.2 and later) system extension that allows applications to pass audio to other applications.
ogg vorbis quicktime component, ogg-streaming works with quicktime-player, but not with itunes
QTCoffee is a set of command-line Mac OS X utilities for manipulating QuickTime movies and other QuickTime readable media.
Browse your iTunes Collection by Cover (OpenGL Animation)
Simple but good RSS-Reader for macosx