The office 12 Excel blog is one of my favorite MSDN blogs, along with Alex and the popular favorites.  The latest Excel post delves into the design process with a focus on the incremental formalization of artifacts.  I love that Microsoft's embrace of blogging allows us to offer insights into the design process in a way that's both interesting and positive for product awareness.  Here's a very cool pic from the post:

While tablet mode is a bit under-used in the search world, hand drawn flow charts and UI mockups seem to drive most of my fellow PMs to swivel and risk losing the wacom $35 pen ocassionally.