Fox, the main point being emigration, the second, raw materials. By the megaton. Bio-engineered pharmecuticals, Pure Crystals of some of the more exotic minerals. Perfectly round ball bearings, alloys not possible on earth. If we show the world what self limited population growth can do for all of us, would it work?

Look, I recall a debate on NPR Science friday where all parties agreed the are simply insufficient raw material available for every family on earth to own a washer and dryer. Mundane point; maybe, but it shows the problem and the potential.

And to go further, experiments with Anti matter, fusion, ETC.