Turn the Sol system into a Dyson Shell
We'll have the equivalent of 5 billion Earths to roam about on
(if you still want to be a biological, that is) controlled weather
systems (if that will even matter by then), and no space rock
threat (they'll all be bricks in the Shell).
We can't keep living and acting the way we do and expect
life to go on just the same as it has on this single planet.
We need to do something radical, and sooner than later.
One trillion satellites for making a shade - that's just a start.
http://www.aeiveos.com:8080/%7Ebradbury/MatrioshkaBrains/index.html