A couple of iTunes plug-ins I have been playing around with:
It can also upload the song via FTP to a server, so you can display the information on a website. The plug-in also retrieves information from Amazon, such as an image of the album cover art and a link to the Amazon product page, prefaced with your Amazon affiliate ID. It can also be used a a podcasting tool, although I prefer to use FeedDemon for that purpose.
Audioscrobbler plugs into iTunes and sits in the background, building your musical profile based on the songs you play.
This profile is sent to the Audioscrobbler server, where you can view your statistics, be matched to people with similar musical tastes, have songs and artists suggested to you and a lot more. It's Open Source, which opens up a lot of possibilities, and there's development happening on Sourceforge with it.
technorati tag: iTunes