http://kerbalspaceprogram.com/This is a new indie game which follows the fledgling space program of the citizens of planet Kerban. You need to design a rocket that allows you to take three brave Kerbals into space and, hopefully, back home safely. The game is in pretty early development, so there aren't too many options yet. I was able to get my astronauts into space after a few tries, and I even achieved an orbit once. Unfortunately I didn't design that rocket correctly, so I was stuck with the full rocket in orbit; I couldn't even decouple the thrusters so I could go home. I ended up just blowing all my fuel, broke out of orbit, and flew off into space forever, as
Space Oddity played in my head.