I came across the Make: site through one of my RSS feeds, and it has quite a lot of interesting projects and podcasts on it. The site has quite a few projects for/using the iPod, including an iPod based stethoscope which can be used to record and playback heart sounds, a USB adapter and charger kit among many others. There are also many other projects like an open source mp3 player, an alarm clock that runs away and a wifi liberator.