The key to space settlement is inexpensive, reliable launch from Earth to orbit. The least expensive, and IMHO most exciting, vehicle today is the SpaceX Falcon. The Falcon 9 has flown a couple of times and is priced at about $5,000/kg, which is well below other launch vehicles. The Falcon Heavy is in development and promises to lower costs even more, to as little as $1,500/kg. The Falcon 9 and Heavy are expendable launchers, meaning the vehicle does not survive the launch and a new vehicle must be built for the next payload. If it were possible to use these vehicles over and over, without too much refurbishment between launches, costs could be dramatically lowered.
I just listened to a talk by Elon Musk, the head of SpaceX. He says that analysis and simulation suggest that they can fly the Falcon 9 first stage back to the launch pad and, with a heat shield and aerodynamic exterior, get the upper stage back as well. He also says that it will be difficult and they may fail, but they intend to try. He estimates the reduction in cost at about 100x. That means SpaceX thinks they can get costs down to around $60/kg.
They could easily be wrong, but if they are even in the ballpark this is revolutionary -- and the 1,500 employees at SpaceX are going to try.
Is there something you can do to help? If you are a US voter, yes. Contact your congressional representatives and ask them to insist that the air force buy launch services with a free and open competition.
Background: The air force launches many satellites into orbit. They are proposing a sole source, non-competitive contract with a consortium of Lockheed and Boeing to buy all of their launches through 2018. If this contract goes through, SpaceX, or any other company, would not be allowed to bid. This is in spite of the fact that SpaceX is cheaper and the Falcon vehicles are built entirely in the U.S. whereas one of the vehicles in the sole source contract, the Atlas V, has a Russian-built main engine! In other words, the air force is insisting on buying Russian engines rather than American products!