Oliver Steele has added an interactive booklist to his blog (scroll all the way to the bottom on the left). He has a wonderful description of how it was developed — only 42 lines of code, written in Laszlo. It’s pretty nifty, and especially useful for a long booklist.
Its neat to see this kind of leight-weight user interface in a rich internet application. Immersive experiences are great, but its also good to remember that we can add fluid and elegant user experence to augment an HTML page. I like Oliver’s approach of blending the background of the app seemlessly in the web page.