Also, someone asked about running sheep in as a vista sidebar gadget (but I could not find the message to reply too).  This has already been done, and works quite well once you copy the .SCR into the windows\system32 directory.  The gadget is available at http://blogs.msdn.com/markhsch/archive/2007/02/28/my-screen-saver-vista-sidebar-gadget.aspx. Of course you loose the ability to up/down vote since it runs the screen saver in "preview" mode, but it sure is better than the static picture viewer.