What is Windows SideShow? Check out WindowsSideShow.com
If you're new to Windows SideShow and want an overview of the feature, or if you're trying to explain to all your friends what exactly that little LCD on the lid of your laptop does, send them over to WindowsSideShow.com. Yes, it is just a fancy redirect to the section of the Windows Vista site that explains SideShow, but it's a LOT easier to find! (I mean seriously, do you remember this URL? I don't.)
By the way, while you're there, let us know what other kinds of information you'd like to see on the site. We've already been able to make a number of specific improvements based on your feedback (see the Windows SideShow row in the Compare Editions table, for example). Just use the "Contact" link on this blog to let us know your thoughts, or send your feedback to sshowext at microsoft dot com.