Yesterday, Microsoft has released the new version of the Posterpedia App. This is very nice app, available in the Windows store. Server Posterpedia is an interactive app that uses technical posters as a reference for understanding Microsoft technologies.
There are posters available for Microsoft Hyper-V, Exchange, Server 2008, SharePoint, Windows Azure, SQL, etc.
You can download the app using the following URL: http://blogs.technet.com/b/windowsserver/archive/2012/11/20/server-posterpedia-v2-available-in-the-windows-store.aspx or in the App Store!