If you could be a fly on anyone's wall at any point in history where would it be, who would you be listening to, and why?

April 9, 1865. Appomattox Court House. I would love to know what conversation(s) actually transpired between Union General Ulysses S. Grant and Confederate General Robert E. Lee. I have read many accounts of the day, but I have always wondered what else was said between these two great men privately.

General Dwight David Eisenhower leading to and during Operation Overlord