I am a former Xanga user. My favorite feature of Xanga was the Currently Reading, Watching, Listening section you could add to a post. In the post editor there was a section to search Amazon for movies, books and CDs. You then were given a list of results. You selected the one you wanted and it appeared at the top/bottom of your post (not included in the RSS feed, which I really liked). You could even link your Amazon Associates account to it.
I would love to find a plugin that did exactly the same thing for WordPress. Has anyone made one?