Fredo's death in Part II is just about the most powerful scene I can think of in cinema history. Whenever I'm trying to think of why GF is my favourite film(along with Part II of course), I just think of that scene. The sound of the birds flying away from the sound of the gunshot still haunts me.
"Tom, you know you surprise me. If anything in this life is certain, if history has taught us anything, it's that you can kill anyone."
