re: The volume of the works of Man
Recorded history until 1950 AD could probably fit on a single floppy disk. Today, I believe we can purchase the entire literary works of mankind on CD Rom for about $1 million bucks. If the trend continues, our very conversations will be recorded (text messaging), and we will continue to develop storage media that can handle it all, and then some.
Losing the physical Earth might not be such a huge loss 5 billion years from now. We may still possess it in fact, in exquisite detail.