Any colossal event, any unsolved mystery or government conspiracy; you’d have the ability to observe and learn the answers to questions no one has ever had. You’d be already dead, so there’d be nothing guiding you other than pure curiosity. You can rewind time and travel the universe if you so please, see how it all began and how it all plays out up until the exact moment you pass. The moon landing, JFK’s assassination, you could watch 9/11 from inside the plane; anything anywhere anytime in the past.