Around the same time I purchased the Mac, we also purchased an Airport Express so that we could stream music from our computers to our stereo.

It was something of a disappointment to learn that by default, you can only stream music to the Airport Express via iTunes, and that you can only use natively supported music formats to boot (such as MP3). I don't use MP3- I haven't for years - I use OGG Vorbis (which I am not about to give up).

I can add OGG support to the Mac (via a Quicktime plug-in), and this lets me play OGG Vorbis music in iTunes, but as soon as I select the Airport Express the music reverts to coming out the computers speakers. Bummer++.

Well, I have found the solution: A product called Airfoil. It will take sound produced from any application (Mac or PC, iTunes or not) and stream it to the Airport Express. Excellent.

I like it so much I thought it was worth plugging it.