Apart from some memorable trips one of the simplest things in flying still gives me a 'Wow' moment every time. Take off on a miserable day with low overcast and climb on top. As you break out the world changes from gray and miserable to sunlit and brilliant white. It's like flying in another world and you kmow that only you and other pilots are going to share that view. Unless you count squinting through a window in a pax jet.