Somehow all of his projects tie together to build a full Mars infrastructure including solar energy, solar mobility, high speed tunnels, space travel and even that satellite network he planned to beam internet to earth from LEO. If he manages to do that in his life time and Mars becomes a popular alternative to Earth, his wealth (or that of his descendants) will exceed anything there ever was. Rockefeller, Carnegie, Vanderbilt and JPMorgan in one person. Of course, it's highly unlikely and just a though experiment at this point.

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