Any object in the cockpit would be able to cast or receive shadows. This depends on the location of the sun shining through the cockpit windows. At the moment the cockpit looks a bit flat, this feature would make it more dynamic.
P3D is a well known example of using this and it looks absolutely STUNNING.
Here’s an example of this in the PMDG 777
source: http://downloads.precisionmanuals.com/images/forum/777/7P3D/PMDG_777LR_P3D_8.jpg